GPU advice for older CPU?

I need to update the GPU in an older computer (amd athlon 4200 x2) and heard that a superfast new GPU might no live up to it’s potential due to the slow CPU.

This probaly also depends on how CPU bound my synth is, but is there a rule of thumb which GPU would make sense for such an old system?

8800gt
GTS250
GTX260
GTX260 (216 cores)
GTX275

PS: My power supply is 500w (newegg.com/Product/Product.a … 6817151043), not sure if it covers the power requirements for the newer cards

thx
Akeem

Can’t really answer the question about the older CPU vs new graphics card. But, I can answer the power supply. I have 500w supplies in my systems and then power a quad core, 1 hard drive, 4 GB of RAM and a GTX 275 no problem. I have a UPS with a power draw display and it shows my total power draw being about 230 watts for 1 system.

Nah there’s no rule of thumb. As you said it’s entirely dependent on how CPU bound your system is. A older CPU can make use of the highest end GPU, if the shaders are heavy enough.

thx guys