Hi, I'm in the process of upgrading my computer to be able to play the latest games again. I'm looking to get the most bang for the buck. So this is what I've decided for the moment:

Abit AB9 Pro
Intel Core 2 Duo E6600
Corsair TWIN2X 6400C4 DDR2, 2048MB CL4, E.P.P Technology
PowerColor Radeon X1950XTX 512MB GDDR4 or Asus GeForce 7900GTX 512MB GDDR3 (about the same price)

I need some good advice now:

1. I've heard that the Abit AB9 Pro has a lot of problems related to memory (especially Dual-Channel) and overclocking. Is this true? If it is, what should I choose instead?
2. I'm not to sure about the memory, it's very expensive. Will I really experience a huge difference in gaming with this memory compared to the much cheaper: Corsair Value S. PC5300 DDR2 2048MB ?
3. Are there any obvious bottlenecks in the configuration above?
4. Any better ideas? Or general advice?

I would say go for the GIGABYTE GA-965P-DS3 and OCZ Gold 2GB (2 x 1GB) DDR2 800 (PC2 6400) kit it seems to be a budget-friendly overclocking setup...

Despite the $30 MIR on the AB9 from newegg, it is tempting but check out hardforum's "Conroe OC database" the DS3 is all over that board but no AB9? May not be too budget friendly when you crank up the Ghz :x

Also do you have a decent PSU to handle the x1900xtx? Nothing worse than playing your fave game and hearing "pop" and waiting for a new PSU

Thanks for your reply. I'll go with the Gigabyte GA-965P DS3 and the cheaper RAM. About the PSU, I need to change that to I guess, any suggestions? I've heard Zalman makes good PSUs.

Zalman is great, but a bit expensive - like Seasonic PSUs you have to pay the piper to get quality.

Check out the Sunbeamtech NUUO 550w it's only $75 shipped, read jonnyguru's detailed review here it got excellent marks.

The OCZ GameXtreme 600w is also an excellent unit, at $110 shipped w/ $15 MIR from zzf that is a tough deal to beat as well. I could not find a review on that particular unit but hexus.net did a 600w-700w PSU roundup and included the big brother OCZ GX 700w and it was the most efficient of the bunch, it even surpassed the FSP700-GLN which is the OEM model it is based from!

I just realized something. If I install Vista some day, will I experience problems since i read that Vista is 64bit and Core 2 Duo isn't a real 64bit chip?

No the EM64T is full 64-bit, check out Intel® 64 Architecture.

Maybe you're thinking of the Itanium which was 64-bit with no 32-bit support?

Yeah, got things a bit mixed up i think, hehe