should i disable nvidia TurboCache with 512 mb of ram?

Benchmark the card in a game with it both on and off. Then choose which one gives better results.
Intuition tells me that it's a good thing, but it doesn't hurt to experiment.

Also, +1 for the gtx 260. Get the 1gb version btw, higher bandwidth in addition to more memory.

Dark
im afraid of 1gb version
i only have 512mb of ram!

It doesn't matter.

The board has it's own memory.

get more ram you will get a prefomance boost cuz 512mb is not so good

i used to have a 1gb burneout lagged on high then i bought a 2gb more (total 3gb)then it runs with out a lag

or are you talking about Vram (vidio memory)

and go for the 460

and btw what
psu
and cpu do you have

i dont thingk you want a bottelneck
or dont have enoth power to 'run' the card

430V PSU
and
Amd Athlon 3800+ 64bit X2
Gigabyte M55S-S3 mobo

gtx460 needs a min of 450W psu



and then you still need to power the rest of your pc (cpu,ram,mobo,fans etc.)
so a 600-700W will be good
and your cpu how fast is it (GHZ)

3800+ :>
2ghz ea core totaling 4ghz!

still not a 4ghz processor :P anyway it will be able to run the gtx 460 but for optimal usage you might want to get a 500w psu in case you have any extras like a secondary hdd or 2 dvd/cd drives

One CD DVD , one HDDm but i have floppy