i have 4 gb of memory in my xp machine and get 3.2 usable in the device manager and also in the bios with my uad 2 card installed

if i put the uad 1 card in the memory drops to 2gb at boot up and also in the bios and in windows even with the 3gb switch enabled and the 3GB /Userva=2900 added

so this one card is robbing me of 1.2 gb, as soon as the card is removed the system is back to 3.2gb. it is the same on all the pci slots

motherboard asus p5 dw delux with the latest bios update

thanking anybody in advance for any light they can shed on this

Sounds about right,
the UAD maps its ram into the machines address space (obviously) and it also HAS to be located within the address space accessible to user space so that the users programs can load the plugin DSP code and data into it (And so that the cards DMA hardware can get at the pages containing the audio data now that IO-APICs have started enforcing that sort of thing).

The 3gb switches give you 3GB of VM available to windows clients and the UAD takes 1.2GB of this for mapping its on card memory, seems perfectly reasonable to me. Does windows not do PAE?

I suppose the UAD drivers could map the card outside the users address space but then every plugin would have to send all requests via the driver (requiring a context switch and possibly a TLB flush (both of which take time)), so mapping the card into the users address space makes sense.

This all goes away of course as soon as you roll with a 64 bit OS that does not have such a relatively small limit on the userspace vm size.

Actually it is Microsoft that is robbing you of VM, not UAD, not that that is much comfort.

Regards, Dan.

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Audiophiles use phono leads because they are unbalanced people!

It's always done that, as far as I can remember.

This should give a rough answer : http://www.vistaclues.com/reader-question-maximum-memory-in-32-bit-windows -vista/

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ScanProAudio & 3XS Audio Systems
ScanProAudio Blog

...or you could always read my explanation from this August 2008 PC Notes column

www.soundonsound.com/sos/aug08/articles/pcnotes_0808.htm


Martin

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YewTreeMagic

so the new question is it better to remove the uad 1 card that i dont use very often and get the extra 1.2gig of memory back and start buying non dsp plugins ? bearing in mind ive got 90% of the uad ones i like.
or leave the card in and live with 2gig of memory(1.5 gig usable with the os taking 500 of it)

Option C.

Install Windows 7 64bit and up the physical memory in the machine.

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ScanProAudio & 3XS Audio Systems
ScanProAudio Blog

installing windows 7 ...... i dont think that would be a very good option for me ,i've talked to my sound card company and he said that i would not get as low a latency with windows 7 without an serious upgarde to my machine and even then i might not get the same latency with my firewire sound card.
on the Dpclat latency checker i get 4-24 micro seconds.in xp with my 2.4 dual core.
giving me a good latency for drumming with bfd2
so i relly dont want to trade my low latency for just being able to access a bit more memory.