P5ND2 SLI Deluxe - OC?

OK,
From what I can tell the SLI mobos don't OC very well. The rest of my system is pretty set:
EE P4 3.73GHZ 1066FSB 2MB L2 Cache
1GB (2 X 512MB) Corsair DDR2 675 PC2 5400 3-2-2-8
7800GTX KO
(2) 74GB Raptors @ 10K in 0 Raid

I fear the Mobo is my main draw back. Since I am not running SLI I was thinking about the P5WD2.

I am on coolmaster water wich is great.

Looking to OC as much as I can with setup.

Any suggestions would be appreciated, thankyou

If I do switch out the boards (gonna need some help with that - water cooling and all) should I change the RAM to PC 8000? Way higher latencies but 1GHZ speed. Which would be better for OCing?

Also, I know this is a stupid question and nearly impossible to answer but what kind of OC sould I expect with the new setup? Thanks