New Gaming Rig: AthlonX2 6400 v.s Q6600

[bca11]

I'm looking for some advice on putting together a gaming rig. The main thing I want is Crysis at good FPS in 1680x1050. I intend to get 2 8800gt video cards. There are a couple of things I need advice on though. One, 64 bit OS would let me use more RAM than 32 bit OS (I'd like 4Gb), but has compatibility issues. Is it safe to go with Vista 64 bit yet in terms of general compatibility? Also, I am torn between two builds that seem good to me. One uses the Athlon X2 6400 and the other the Q6600. Which would be better for a gaming rig. Would the Athlon be a bottleneck for 2 8800gt's? Would it be enough for Crysis in DX10 to produce decent quality settings and good FPS?

Here is what the rig will look like.

Athlon6400 or Q6600
4GB DDR2 800
Dual 8800GT
Microsoft Windows Vista Home Premium 64bit or 32bit
550watt Cooler Master eXtreme Power RS-550-PCAR

[odannyboy000]

Go with the Q6600, it's faster.

If you are worried about a 64-bit O.S. being problematic then you should just dual-boot XP and Vista, that's what I do. I must point out that I use Vista instead of XP and it has been compatible with pretty much every kind of software I throw at it. (There were definitely some cases where I had to do google searches to fix problems with software, though)

[George Hallam]

Go with the Quad core, the 6400+ is not a bad CPU but the Q6600 has alot more potential, will last longer and has more raw power.

The 8800Gt's will be the bottleneck for crysis. I run crysis with my rig (see below) at 1680 x 1050 with 4x AA, 16x AF and i get 25-27 FPS by far the graphics card is the bottleneck

[bca11]

If one 8800gt is a bottleneck, would 2 still be?

[Ajmukon]

... i prefer ONE card... (one more expensive card)
but .. two is better...

Get a 8800GTX 512MB.. or 612MB

[bca11]

Ok so would it be possible to fit a 9800GX2 in this comp, or is the power supply not up to the task?

http://www.newegg.com/Product/Product.aspx?Item=N82E16883103133

[George Hallam]

yes it would be fine.Make sure the case is big enough

here a chart to prove the power consumption

http://www.hothardware.com/articleimages/Item1126/power.png

EDIT: is that the system you are buying in the link?