What speed should I buy for this rig?

I am pretty sure of the answer; I just want confirmation before I order the memory.

I am planning on watercooling a pelt on the following system:

Asus A7V8X-E Deluxe
Barton 2500+ (333mhz)
ATI 9600 Pro

I did read the memory faq up top (very well laid out), but didn't find my situation addressed.

This system was hitting 3200+ (400mhz) with no problem on air cooling, using Buffalo Tech PC3200 Winbond chips.

But now I will be attempting to go much higher with the TEC. As I raise the cpu speeds as high as I can take it, shouldn't I probably be running PC4000 or so to ensure the memory won't hold me back? The only reason I am doublechecking is because the mobo specs stop at PC3200.

Thx.

Well most mobo's stop at 3200, but you must overclock it through bios to reach 4000 speeds.

So I guess you're saying buying PC4000 instead of PC3200 is the way to go?