Pentium D 3.2 GHz

Why buy an old tech processor?
Core 2 Duo is the way to go.
Very cheap called Pentium Dual core
E2140, E2160, E2180, E2200

Low budget C2D:
E4500, E4600, E4700

Mainstream C2D:
E6550, E6750, E8200,

Performance C2:
E8400, E8500, Q6600, Q9300, Q9450

We need info on your hardware so we can help you choose.
Motherboard maker + model
RAM you said 1GB DDR2 (single or dual channel)?
LCD/CRT + resolution
Geforce 8600GT and 8800GT are worlds apart.
Upto 1280x1024 screen resolution and low details you could go with 8600GT. Anything above that and 8800GT is the way to go.

Since the Core2 architecture is vastly superior to the Pentium D and the Core2 can be bought for so little, there shouldn't be any reason to get a Pentium D (not the same as Pentium Dual Core which is actually a cheap Core2). You need to make sure your motherboard will support a Core2, but any moderately modern chipset will.

-mcg

Well it's Pentium D is cheaper and can do the work all i need is to change the graphic card. The motherboard is foxcon. chipset is intel 945 G or smth like that and support C2D processors
Thx for the advices

I can't wait to get rid of my Pentium D.
It's so hot I can't run the PC longer than about 15mins without having to open the window!

wow man where you live ?   i use my old prescott to warm my rooms in winter always too hot

I can't figure out why you'd buy a Pentium D such as the one here:
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

The c2d E4500 (http://www.newegg.com/Product/Product.aspx?Item=N82E168...) is actually 5 bucks cheaper and fits in the same socket as that Pentium D processor.

If you look at the following chart, you can see that he E4300 (400 mhz slower than the E4500) outperforms the PD935 by quite a bit, even in games: http://www23.tomshardware.com/cpu_2007.html?modelx=33&m...

I highly recommend the E2160 - http://www.newegg.com/Product/Product.aspx?Item=N82E168...

$70 - cheap as chips. Overclock it to 3ghz or so. Means you could get the 8800GT with the saved money.