Re: What is the PerfLevelSrc hack ?
I've used Beryl/Compiz on low-end nVidia cards (5200, 7300) to high-end (7950+) and there is a tremendous difference.
Then again I'm using super hi-resolutions with two monitors and normally 10-20 apps running. That kills the low-end cards even on some 2D stuff.
However, even on a laptop Beryl will give those low-end cards a workout. I'll speak hypothetically and say that it is doing lots of up and down clocking, which maybe the driver is not 100% stable in doing it.
XID errors typically mean the driver received a hardware error. I normally see them when the cards are overheating or about to die (two have died when lots of XID errors started happening). Tweaking the driver to "reduce" XID errors is only delaying the inevitable.
Yes, he will have to buy better hardware. Why are you so cheap? Spend an extra $100 and get a chip that is twice as fast, won't overheat, and will last you a while.