There may be some possibility as Cubase 6.5 is not officially supported in XP either, but it runs just fine here.
It can be run ok but if it goes wrong it's definitely Cubase and not the machine, right? (if we were on the Steinberg forum)
Try to run it in a way that when a crash occurs you're pretty sure it was one of maybe three things max if you want it fixed without buying a whole new rig.
Success is round the corner. It's also round the bend.