Mem settings lower than rated on Corsair XMS LL

I'm using Corsair DDR400 XMS LL with a 2.4c and ASUS P4C800.
Settings:
2.4 @ 3.0 (250mhz fsb)
320 memory divider (5/4)
1.6 vcore
AGP v 1.6
mem v 2.75
2-2-2-5-4

Corsair says the rated timings are: 2-3-2-6

The system runs SETI 24/7 but it may lockup twice a day. Could this be because of the lower set timings? Maybe i need more mem. v.? What should i try next to make it more stable?
I like the bandwidth i get with these settings being: 5426/5429

Hard to say, it could be your memory or your CPU. Try setting the memory to stock timings and see what happens. If your computer still locks, try clocking your CPU down.

I'd say give it a shot at 2-3-2-5...in my experience, that should be stable.

I would try 2.85v

I would check the memory with memtest86.

RAS to CAS (tRCD) shouldn't be set lower than 3 on 875/865 boards.

-Bobby