Hi folks!

I'm publicising Thesycon's DPC Latency Checker ( www.thesycon.de/eng/latency_check.shtml ) in my next PC Notes column, but various posters here are already finding it useful for exposing problems that may cause audio clicks and pops, so it would be good if we could gather some initial results from various systems to give us all an idea of typical figures and what happens to them with rogue hardware.

DPC Latency Checker is a tiny 310KB Windows utility, doesn't require installing (just double-click the file to run), and is really easy to use. It polls the DPC (Deferred Procedure Call) latency once every second and displays the results in a horizontally-scrolling graph. Hardware drivers issue periodic interrupts, and Windows deals with these as soon as it can on a first come first served basis (the DPC).

Unfortunately some hardware spends too long dealing with its DPC routine - readings under 500 microseconds (the green zone) are fine; those between 500 and 1000 microseconds (or 1mS) are borderline, while those beyond these (the red zone) may result in audio interruptions.



The beauty of this tool is that you can spot occasional spikes above the norm and see how often they occur, which can be a great help in tracking down the culprit. If you measure occasional high peaks you won't be able to run your audio interface at such a low latency, and should disable individual devices one at a time in Device Manager to find out which one is causing the problem.

Please post your measurements here so we can build up a useful resource and possibly track down some common causes for these spikes, including particular laptop models, MIDI interfaces, BIOS revisions, wireless network adaptors, and so on


Please include:

1. Your PC hardware: CPU, motherboard, RAM, and Windows version.

2. DPC Latency typical and peak values.

3. Any other relevant hardware that might be responsible.

Many thanks!


Martin

--------------------
YewTreeMagic

OK, here we go with my results:

Hardware: Intel Conroe E6600 2.4GHz dual-core processor, Intel DP965LT motherboard with Intel P965 chipset running 1066MHz system Bus, 2Gb Corsair PC2-6400 DDR2 RAM, and Windows XP with Service Pack 2.

XP General install (Internet-enabled): typical 50 microseconds, occasional peak up to 100 microseconds

XP Music install (stripped-down music-only partition): typical 24 microseconds, occasional peak up to 65 microseconds.


Although both sets of results are absolutely tiny, you can already see some measurable benefits from employing a stripped-down music-only partition if you want to run your audio interface down to a really low (almost real-time) latency.


Martin

--------------------
YewTreeMagic

Its a very cute utility, thanks!

Now, i will publish my results only if you promise not to make any wise cracks about my rusty old gear!

Desktop -
CPU - Intel Northwood (Pentium 4 Single core) 2.4Ghz
MotherBoard - GigaByte GA-8PE667
Chipset - Intel Brookdale i845PE
Memory - 1.5GB DDR at 200MHz
OS - XP Pro (SP2 for the Internet Boot / SP1 for the Music Boot)
Main SoundBoard - FW Mackie ONYX 1640

Results -
Internet Boot - around 330 microscnds with peaks up to 500.
Music Boot - around 75 micros with peaks up to 100.
-----------
Laptop -
CPU - Intel Dothan (Pentium M725 Single Core) 1.6GHz
MotherBoard - HP Presario 2200
Chipset - Intel Montara GM-i825GM
Memory - 1GB DDR at 200MHz
OS - XP Home (SP2 / SP1)
Main SoundBoard - FW M-Audio Ozonic

Results -
Internet Boot - 180 up to 220
Music Boot - around 70 with noticeable peaks at 475.

I would look into it but im throwing the damn thing anyway , and i will certainly use this DPC checker when laptop hunting.

--------------------
The Man in the Crowd with the Multi Colored Mirrors on his HobNail Boots

WoHoHo !!

I did bother to check,
It was the DVD Combo Drive - DPC Latency went right down to a steady 35 micros - no peaks at all!

Thanks Again!


--------------------
The Man in the Crowd with the Multi Colored Mirrors on his HobNail Boots

I've used this for a few months and here are my findings:

Hardware: Intel Q6600, ASUS Commando motherboard with Intel P965 chipset running 1066MHz system Bus, 4Gb Corsair PC2-6400 DDR2 RAM, and Windows XP with Service Pack 2.

Music-only DAW: typical 20 microseconds, occasional peak up to 45 microseconds.

However the biggest finding was the effect of enabling the ethernet controllers; typical rose to 250 and peak to 612. The Marvel Yukon ethernet controllers are normally disabled in the device manager.

Loooking at the two controllers on my mobo in turn the biggest culprit was from the Marvel Yukon 88E8001/8003/8010/PCI Gigabit Ethernet Controller producing peaks of 500 microseconds every two seconds.

Less problematic was the Marvel Yukon 88E8056 PCI-E Gigabit Ethernet Controller although interestingly this generated a regular sawtooth pattern peaking at 400 microseconds every every 5 seconds.

Since I'll have to enable one of the ethernet ports once the Euphonix Artist controllers arrive on PC I'll have to look at this again. There may be settings for these ports that need optimising but until then I keep them disabled.

Regards, Andrew

Are you meant to run it while the machine is idle? I get much lower numbers: 3us mostly with peaks to 13us on my AMD X2 4400+ / Asus A8V.

I only ran it because I also have the Marvel Yukon 88E8001/8003/8010 ethernet controller mentioned in the previous post (and it is enabled).

I have

Intel E6600
Asus P5B Deluxe WiFi
2Gb 800Mhz CAS4 RAM
Windows XP SP2
Gigabyte geforce 7600 video card
Creamware SCOPE home PCI card

I see an average of about 70us with a peak of 156us. I've made the usual tweak of background services & turning off the on-board audio. I do have a firewall and anti-virus running though as I keep the internet on.

If you get good DPCLAT results but still get the odd intermittent click, another tool you might want to look into is systinternals process explorer. If you double click on the system process, look at threads and rank by cpu utilization, the module that is causing problems will sometimes pop to the top of the list in time with the clicks.

Edited by markhodges (06/03/08 10:23 PM)

Thanks for the results so far - most illuminating

Boywander - that's a gratifying result. I wonder if your DVD Combo drive is the offender, or its drivers, or a Windows setting? Let us know if you discover more.

ASG - network hardware seems to keep popping up as a major headache in some music PCs, with wireless network adaptor being the worst offenders.

cc. - personally I ran my tests while running my sequencer through a typical song. The measurements when idle on my PC weren't really any different, but being in a real-world scenario seemed the most appropriate method just in case anything kicked in.

mark - I use Process Explorer myself. DPC Latency is more likely to highlight hardware device issues, while Process Explorer may also help you track down rogue software tasks, but can be more difficult to use.

Keep those measurements coming!


Martin

--------------------
YewTreeMagic

Hi,

Gigabyte P35-DS4 Rev 1.1
Q6600 2.4GHz G0 Stepping
2Gb 1066MHz 5-5-5-15 OCZ memory
2 x Pioneer IDE DVD writers
Hitatchi 7K250 SATA HDD 500GB
XP SP2 with all latest patches

Results:

1) BIOS F6 and above - regular peaks of at least 695us. Major timing problems with Cubase 4 and pop/clicks when accessing HD and playing back.

2) BIOS F4 or F5 - between 30 and 40us typically, odd peak to 77us. Has once or twice peaked to 252us on disk access / program load very occasionally.

3) The above measurements were with USB connected Virus TI Polar turned off. With Polar on (and F5 BIOS) varies all over the place between about 95us and max of 161us whilst playing back in Cubase.

Interestingly I haven't noticed any difference in DPC timings when disabling any device including network aside from the Virus. I am currently discussing DPC issues with the BIOSes >F5 with Gigabyte.

Cheers.

Edited by HL (06/03/08 10:59 PM)

My Results:



Average latency of 10 microseconds, spikes to around 20 microseconds. This system performs very well.

E6600
Intel DQ965GF MicroATX motherboard
80 GB Maxtor System drive
250 Maxtor audio drive
500 WD Caviar Samples drive
500 Gb Seagate backups
Two Sweex Via PCI Firewire cards
One ST Lab External SATA PCI express card
RME FIREFACE 800
Liquid MIx
BCF 2000
M-audio MIdisport 8X8
NI Kore

My Dell laptop performs not so well. I'll post that next.

Here's the Dell laptop:



This is a Inspiron 1520 (I think the closest thing now is the Vostro 1500)

T7500
4 GB RAM
160 GB Hardrive

I had to reinstall everything twice before I could get it like this. First time I had huge latency spikes, now it stays at around 160-200 microseconds most of the time. With my Fireface it plays well, but let's see with the Audiofire 2 that's arriving tomorrow.

Quote Martin Walker:

---

mark - I use Process Explorer myself. DPC Latency is more likely to highlight hardware device issues, while Process Explorer may also help you track down rogue software tasks, but can be more difficult to use.

---

True, however DPC routines sometimes have to pass work to other threads because of constraints on what can be done at the DPC interrupt level e.g. accessing paged memory. A driver will often create these threads with a higher than normal priority. I found using process explorer to look specifically at the threads in the 'system' task can help identify these worker threads and the driver responsible for creating them.

Here are my (horrifying) results for my Music notebook and two other (non Music) notebooks as well (ASUS and Sony) for comparison.

I. COMPAL Centrino Notebook CL50 (dual boot configuration)
CPU – Intel Banias Pentium M 750 @ 1700 MHz, 398,7 MHz FSB
Mainboard – COMPAL CL50
Chipset - Intel i855PM
BIOS – COMPAL v 1.60, Insyde Software SMBIOS for Whitney
Physical Memory – Kingmax Semiconductor, 1024 MB (2x256 DDR-SDRAM PC2100, 133 MHz)
Video Card - ATI Mobility Radeon 9000
Hard Disk – HTS726060M9AT00 (60GB)
Hard Disk - Maxtor (251 GB)
DVD Rom Drive – TOSHIBA DVD-ROM SD-R6112
Network Card – Realtek RT8139 Fast Ethernet
Network Card – Broadcom BCM4306 802.11g Wireless NIC
Firewire – VT6306 VIA Fire II IEEE-1394 OHCI Link Layer Controller
OS – Win XP Home 5.01.2600 SP2, dual boot (Music & Internet partition)
DirectX- Version 9.0c

Results -
Internet boot – typical around 400 microsec, frequently peaking up to 6225 microsec
Music boot – typical around 500 microsec, occasionally peaking to 2250 microsec
---------------------------------------------------------------------------------------- ------------------------------
II. ASUS Centrino Notebook M6N (only for wireless internet use)
CPU – Intel Banias Pentium M 750 @ 1500 MHz, 400 MHz FSB
Mainboard ASUSTeK Computer Inc. M6N
Chipset - Intel i855PM
BIOS – American Megatrends Inc. 0208, 6-5-2004, SMBIOS Version 2.3
Physical Memory - 512 MB (2x256 DDR-SDRAM PC2700, 166 MHz)
Video Card - ATI Mobility Radeon 9700 (M10 NP) (RV350)
Hard Disk - IC25N040ATMR04-0 (40 GB)
Hard Disk - Samsung (120 GB)
DVD Rom Drive – TOSHIBA DVD-ROM SD-R2512
Network Card – Broadcom BCM5788 NetXtreme Gigabit Ethernet
Network Card – Intel PRO/Wireless 2200 BG
Firewire - RL5c552 IEEE-1394 Controller
OS – Win XP Prof 5.01.2600 SP2
DirectX- Version 9.0c

Results – typical around 82 microsec with occasional peaks up to 285 microsec
---------------------------------------------------------------------------------------- --------------------
III. SONY VAIO Notebook VGN A217S (only wireless internet boot)
CPU – Intel Dothan Pentium M 735 @ 1700 MHz, 398,7 MHz FSB
Mainboard – Not specified
Chipset - Intel i855PM
BIOS - American Megatrends Inc. R0080F1, 28-9-2004, SMBIOS Version 2.3
Physical Memory - MB (2x256 DDR-SDRAM PC2700, 166 MHz)
Video Card - ATI Mobility Radeon 9700 (M10 NP) (RV350)
Hard Disk - TOSHIBA MK1031 GAS
DVD Rom Drive – TOSHIBA DVD-ROM SD-R6112
Network Card – 82541 EI Gigabit Ethernet Controller
Network Card – Intel PRO Wireless 2200BG
Firewire – PCI7x20 1394a-2000 OHCI Two Port PHY/Link Layer Controller
OS – Win XP Home 5.01.2600 SP2
DirectX – Version 9.0c

Results -
Internet boot – typical around 170 microsec with occasional peaks up to 285 microsec


I have also used Process Explorer to find any clue for the DPC's, but no specific conclusions can be made for the COMPAL CL50. Still no solution for the problem.

Jacob

--------------------
Pentium M 1.7 G, 1G RAM, WINXP SP3 dual boot, 60+250+2x500GB HDD, 7200 rpm; Yamaha 01X; Studio Manager/mLan Tools 2.0; Cubase 4.5; Yamaha CP300

Very interesting utility!

My System:

Pentium Core 2 Duo, 2.4 GHz
ASUS P5B Deluxe motherboard (P965 chipset)
2GB Corsair DDR2 800 RAM
2 Western Digital 250GB HDs
Antec Neo 550 (550 watt) power supply
ATI Sapphire Radon 1300 graphics card PCI-e 16X
Belkin Wireless network adapter
RME Fire Face 400
Windows XP professional

I use this computer as a music workstation and general use/internet system. So far I haven't had any problems with droupouts or clicks etc so I don't bother turning of the network adapter or any services such as the firewall or virus scanner.

When I first ran the DPC Latency Checker things were crusing along at 5 to 80us then BAM! Two spikes - 2000us then 5300us - ouch! They reoccured every 20s or so.

The first thing I turned off was the network adapter and the spikes disappeared.

Without the network adapter enabled latancy is 10-80us

I don't know if it will change the way I work but it is nice to know if problems arise.

My laptop:
Dell Precision M6300
T7800 C2D 2.6GHz CPU
4GB RAM
200GB 7k2 rpm HD
DVD +/-RW
Intel a/g wireless
Nvidia Quadro FX 1600M display adapter
Motu 828 MkII
Windows XP Pro SP2

My dpclat results:
repeating 200us with regular peaks up to ~2000us every 15 seconds with some higher peaks, I think the record is currently ~15000us!

And I experience drop outs, or more like strange noises, regularly in Sonar 7 PE, even at low CPU load and high buffer size settings.

I have disabled everything possible to disable in the BIOS, and the remaining unneccessary (and some necessary...) devices in device manager. I have tried reinstalling several times. I have tuned Windows according to the SOS advices and I have tried all available versions of the BIOS.

Conclusion so far: This laptop is not usable for music production.

--------------------
/Lachris
(Mutlicom Kunshan D900 (=Clevo D901C), Motu 828 MkII, Sonar 7 PE)

Quote Nuno_:

---

Here's the Dell laptop:



This is a Inspiron 1520 (I think the closest thing now is the Vostro 1500)

T7500
4 GB RAM
160 GB Hardrive

I had to reinstall everything twice before I could get it like this. First time I had huge latency spikes, now it stays at around 160-200 microseconds most of the time. With my Fireface it plays well, but let's see with the Audiofire 2 that's arriving tomorrow.

---

the Vostro 1500 is essentially an Inspiron without the colourful exterior... but these are fantastic results. my priority at the mo is to get my soundcard working and then i will gladly run the utility to see what i get from my (almost identical) setup.

--------------------
hourglass | random thoughts | doubledotdash!? collective

Quote Martin Walker:

---

cc. - personally I ran my tests while running my sequencer through a typical song. The measurements when idle on my PC weren't really any different, but being in a real-world scenario seemed the most appropriate method just in case anything kicked in.

---

Mine are very different. Running a typical song (maybe 50% cpu load) I get around 30us with spikes to 130us - 10x higher.

Quote onesecondglance:

---

Quote Nuno_:

---

Here's the Dell laptop:



This is a Inspiron 1520 (I think the closest thing now is the Vostro 1500)

T7500
4 GB RAM
160 GB Hardrive

I had to reinstall everything twice before I could get it like this. First time I had huge latency spikes, now it stays at around 160-200 microseconds most of the time. With my Fireface it plays well, but let's see with the Audiofire 2 that's arriving tomorrow.

---

the Vostro 1500 is essentially an Inspiron without the colourful exterior... but these are fantastic results. my priority at the mo is to get my soundcard working and then i will gladly run the utility to see what i get from my (almost identical) setup.

---

It takes some work, but you can get it to work. My first install would not play well with my FF800 or my NI kore, but this one does.

I forgot that mine has the Gforce 8400 128 MB graphics also. I just installed windows, chipset, then soundcard driver and graphics. I think it was in that order.

Heya M


Just to post my reslts on a NON audio pc

Dell Latitude D410 laptop : Intel Pentium M 750 1.86GHz, Intel 915 chipset, 512MB DDR2 mem, XP Pro SP2.


With ALL drivers installed
Office and other non audio software installed.

NO XP tweaks
Antivirus turned ON
Firewalls turned ON
Bluetooth turned ON and wiriting now on this forum


280mS-394mS max 1091mS

"This machine should be able to handle real-time streaming of audio and/or video data without drop-outs."







Can confirm that enabling wifi shoots it beyond 16000mS,
and even after turning wifi off it takes a fair while to settle down.

Great idea to bring awareness to this fantastic utility. As a part-time DAW builder, this tool has been incredibly useful to my work.

I built a new system for own use quite a while back, using the ASUS P5W DH motherboard. This motherboard has an additional hard drive controller by JMicron, and I initially had my audio drive (Western Digital SATA 74GB Raptor) connected to the JMicron drive controller.

During initial testing, I was getting audio drop-outs that I could not account for. Using the the DPC Latency Checker, I could easily see that I had a major problem with a kernel-mode device driver. Having already disabled all other non-essential onboard devices, my first thought was the JMicron controller, and I was right.

After I moved the audio drive to the primary drive controller, the drop-out problem completely disappeared, and I confirmed smooth DPC performance by the DPC Latency Checker.

This tells me that the driver for the JMicron controller for this motherboard is not well suited for digital audio purposes, thank you DPC Latency Checker!

I should also point out that the ASUS P5W DH (BIOS 2302) otherwise performs INCREDIBLY well and is super stable running Sonar 7.0.2 on Windows XP SP2 (and recently with SP3 RC1).

The DPC Latency Checker doesn't even peak above 39 micro seconds when running on this system. (Intel Q6600 "G0" @ 3.0GHz CPU, 2GB Corsair DDR2-800 CAS4 RAM)

-hounDAWg

Thanks for all these results folks - we have already established beyond doubt that for an audio PC:

a) Having Wi-fi enabled is a no-no.

b) Occasionally a rogue BIOS update can cripple performance.

c) Some hard drive controllers need to be avoided.

d) Some laptop models may be fundamentally unsuitable.

Boywander also makes the very sensible suggestion of using DPC Latency Checker when evaluating new laptops - if you pop it onto a USB stick you could even run it on shop models.

tft - thanks for the reality check with your decidedly non-audio laptop and wi-fi results, but it's microseconds, not milliseconds - 16000mS would mean your laptop would grind to a complete halt for 16 seconds

Keep those results rolling in and we'll see what else we can deduce.


Martin

--------------------
YewTreeMagic

I just tried my Dell Latitude D520 (T5500 1.66GHz), on Vista Home Basic straight out of the box with everything enabled I got ~1000us with occasional peaks of 1600us. Turning off the wifi (intel pro wireless) takes it down to around 200us with frequent peaks of 1000us. I haven't tried any music apps on it though.

hi

amd athlon 2.6
1.5 gig 333mhz ram
80 gig ide hdd x2
256 agp 8 card with fan
abit nf7s mobo
motu pci 424 card 24 io 2408mk3

fire wall on
internet connected
radio playing

current latency between 80-196

absolute maximum 355

no radio
current latency between 31-78

absolute maximum 103

necro

Quote:

---

I wonder if your DVD Combo drive is the offender, or its drivers, or a Windows setting? Let us know if you discover more.

---

Its a very problematic Drive, an old Toshiba ODD-DVD SD-R6252. it has a few well known and documented issues. I dont know why i had it enabled, since it barely works anyway. so i guess its the physical (faulty) drive thats the offender here.

--------------------
The Man in the Crowd with the Multi Colored Mirrors on his HobNail Boots

Hi

What a great utility, I seem to get an average of 10 microseconds with a peak of 24, absolute max of 36 - running on a lean xp pro sp2 setup. I had Zonealarm, Avast, and network card running.

Main components:

Intel e6420 Core 2 Duo
Asus P5B E
Corsair 2gb 6400 DDR2
Gigabyte 7300 GS gfx card
Samsung P120 250gb SATA
WD Caviar 320gb Se16 SATA

--------------------
"We deal in junk, you know; What we've got is what other people put in the rubbish bin." - Joe Strummer.

I've got the following:

Dell Inspiron 9400 (latest bios and drivers)
Onboard Intel Graphics
Core Duo 1.6GHz
1GB RAM
60GB HDD (Not sure of the speed... presume it's 5400rpm)
NEC ND-6650A DVD +/-RW
Ricoh F/W Controller (eek!)
Windows XP

Tested using my FocusRite Saffire Pro 26 i/o, recording 3 tracks in Cubase SX3 at 96khz.

I've disabled the dvd drive, ethernet, wireless and the sd card slot. I've also disabled some services, such as the windows firewall and there are no other antivirus/firewall applications running.
The wireless causes peaks of approx. 2000 microseconds if enabled!

With all this disabled, I get:

Average: 200
Max: 700

Considering I've got the dreaded Ricoh firewire chipset, I'm acually reasonably happy with this. I don't get any audio dropouts, which is better than most are getting.
I'm going to do a complete re-install sometime soon and make XP as lean as possible.. hopefully I can significantly improve on the 700 peaks I'm getting.
I'm just waiting for the new quad-core Penryn laptops to become available and I'll be getting rid of this laptop anyway .

Hope this helps.

Cheers,
Binny

Oh.. forgot to mention.. I've got 4ms latency selected for the Saffire Pro 26.

Binny.

Additional result for my Music laptop:

I. COMPAL Centrino Notebook CL50 (dual boot configuration)
CPU – Intel Banias Pentium M 750 @ 1700 MHz, 398,7 MHz FSB
Mainboard – COMPAL CL50
Chipset - Intel i855PM
BIOS – COMPAL v 1.60, Insyde Software SMBIOS for Whitney
Physical Memory – Kingmax Semiconductor, 1024 MB (2x256 DDR-SDRAM PC2100, 133 MHz)
Video Card - ATI Mobility Radeon 9000
Hard Disk – HTS726060M9AT00 (60GB)
Hard Disk - Maxtor (251 GB)
DVD Rom Drive – TOSHIBA DVD-ROM SD-R6112
Network Card – Realtek RT8139 Fast Ethernet
Network Card – Broadcom BCM4306 802.11g Wireless NIC
Firewire – VT6306 VIA Fire II IEEE-1394 OHCI Link Layer Controller
OS – Win XP Home 5.01.2600 SP2, dual boot (Music & Internet partition)
DirectX- Version 9.0c

Earlier Measurements -
Internet (non music) boot – typical around 400 microsec, frequently peaking up to 6225 microsec
Music boot – typical around 500 microsec, occasionally peaking to 2250 microsec

New, additional measurement -
Internet (non music) boot with radio disabled – typical steady around 400 microsec, occasional peaks up to 1182 microsec

So, it seems that my internet boot without radio behaves somewhat better than the lean music boot

jacob

--------------------
Pentium M 1.7 G, 1G RAM, WINXP SP3 dual boot, 60+250+2x500GB HDD, 7200 rpm; Yamaha 01X; Studio Manager/mLan Tools 2.0; Cubase 4.5; Yamaha CP300

Intel core2duo E6850 3ghz asus motherboard 4gb pc26400 ram
4 * 350 gb seagate hd
2 x nvidia 7500 graphics cards
yamaha mlan system with TI chipset on motherboard
one detachable linksys usb wireless node


A maximum with wifi 128
A maximum without wifi 41

--------------------
"A warning , with love and peace"

i mean nvidia 7600s

--------------------
"A warning , with love and peace"

Hp NX7400 Laptop - 2.0Ghz Core2Duo T7200, 2Gb Ram, Windows XP Pro, EMU1616 PCMCIA soundcard

Basic Install, fairly stripped down.

With no soundcard plugged in :

Reading between 4 and 10 typical, with a peak at 17

With Soundcard Plugged in (and song running at 224 samples/6ms) :

Reading Between 85 and 95 typical with a peak of 105

Adding WiFi and Ethernet:

Reading between 123 and 184 typical with a peak of 754

The surprise culprit seems to be the Broadcom 440x Ethernet card - It's just as bad as the Wifi Card

Dell Vostro 1500 laptop.
T7300 2x2.00Ghz
4Gb Ram (3.5Gb Showing)
Windows XP Pro

Music boot:
Normal 90uS
Peak 168uS

(Edit: realised I had the network controllers installed. As soon as I disabled those, it went down to averaging around 30uS)

Normal Boot
Normal 190uS
Peak 337uS

My desktop surprised me - It is permenantly online using the onboard NIC, has AV and firewall running and no tweaks on it whatsoever

Abit Fatal1ty AN8-SLi
Amd Athlon 4000+
2Gb RAM
Windows XP Pro

Normal 15uS
Peak 52uS

--------------------
Is thinking about starting a new project

Edited by Blink (09/03/08 06:31 PM)

Quote Blink:

---

Dell Vostro 1500 laptop.
T7300 2x2.00Ghz
4Gb Ram (3.5Gb Showing)
Windows XP Pro

Music boot:
Normal 90uS
Peak 168uS

(Edit: realised I had the network controllers installed. As soon as I disabled those, it went down to averaging around 30uS)

Normal Boot
Normal 190uS
Peak 337uS

---

Good results. I'd like to get my inspiron like that. What drivers have you installed on it?

Also, what soundcard are you using with it?

This is all interesting stuff folks, and it seems to be making people more aware of rogue hardware devices, which can only be a good thing.

jacob - the fact that your Internet-enabled setup has a lower DPC Latency than your stripped-down music partition should hopefully help you track down the culprit.

Shifty - With Chopsy getting 10 typical and 36 peak with a network card running, your results of 85/105 jumping to 123/754 with the Broadcom 440x Ethernet card suggest that not all ethernet cards are equal in the eyes of the musician


Martin

--------------------
YewTreeMagic

Quote Nuno_:

---

Good results. I'd like to get my inspiron like that. What drivers have you installed on it?

Also, what soundcard are you using with it?

---

I am running an Edirol UA-101 and the drivers that came on the CD. the machine is about 3 months old, so I am not sure how new the drivers are. Disabling both the network controllers made a big difference (especially the broadcom one).

I am also using a little app (can't remember the name now - will check topnight), which keeps the processor running flat out - not sure if that makes a difference

--------------------
Is thinking about starting a new project

Quote Martin Walker:

---

Shifty - With Chopsy getting 10 typical and 36 peak with a network card running, your results of 85/105 jumping to 123/754 with the Broadcom 440x Ethernet card suggest that not all ethernet cards are equal in the eyes of the musician

Martin

---

Yeah - it's the last thing that I'd check when choosing a laptop to be honest !

Luckily I don't have much need for the Ethernet or Wireless cards when making music, so it's not a massive issue (and there's not a lot I can do about it on a laptop!). At least it's not something like a USB controller or disk controller that's causing the jumps.

I'm not sure that the EMU1616 adding such a big chunk of latency is a particularly good thing either. I'm able to get a soundcard buffer size of 224 samples (5.6 ms) but no lower without clicks , which is slightly disapointing for a modern machine.

The NX7400 even has a TI chipset for the PCMCIA card as well


Ah well, at least it all works without pops and stutters!

Edited by Shifty (10/03/08 06:11 PM)

The PC i'm on at the mo (admittedly not my main music pc which i'll check later..):

Intel Conroe E6400 2.13GHz
Mobo: Gigbyte 965P-DS3P
Ram: 2gig DDR2 PC2-5300 (333MHz)
Windows XP pro Service Pack 3

Typically: 10 - 15uS with occasional peaks to 22uS

Maxium: 135 uS

I presume maximum reading should be taken with no programs running. So reading was taken in the time it took me to write this with just DPC latency checker and firefox running.

My laptop:
HP Compaq nc6220
Pemtium M 1.86GHz
1GB RAM
60GB Ultra ATA-100 5400 RPM 8MB
CDRW/DVD-ROM combo
Intel a/g wireless
Built-in Intel display adapter
Windows XP Pro SP2

My dpclat results:
Repeating 20us with no peaks. Except when I move the mouse, it goes to 2-400us (rarely above 275us)

Everything on. Nothing disabled.

--------------------
/Lachris
(Mutlicom Kunshan D900 (=Clevo D901C), Motu 828 MkII, Sonar 7 PE)

Finaly getting the chance to play with my Compaq nx6310 laptop. (Thanks to TFT)

Coupled to an M-audio NRV10 (firewire) I played a Cubase Studio 4 song with 24 audio tracks playing and 8 simultanious audio tracks recording. All networking off. No audio tweeks yet. The machine took it in it's stride.

I got:
Typicaly 75(ish)
Max: 168

With all networking turned back on - though nothing conected - I got:
Typical 140
Max: 224

Moving the mouse made no difference.

The ONLY time I saw it go into the red was when I pressed the wireless activation button after I had re-enabled the networking.

Task manager showed Cubase at about 10-12% CPU ussage.
NRV10 set to 64 samples at 44.1 KHz. Cubase showed Input latency 3.9ms, output 3.9ms.

I'll try it on the desktop PC later on.

--------------------
Ruaridh (Pronounced "Rory").
Cubase 5 AMD Athlon X2 64 5200+. 2 Gig RAM. 2x7,200 IDE drives. Windows XP home sp2. Terratec EWS 88 MT. Guitars, Marshall Amps, Beer.

Edited by Ruaridh (11/03/08 02:37 PM)