Slight stability issues

[Platinum]

Ok so having a few minor stability issues, wondered if anyone can help.
First of all my system is as follows :

Abit IP35 mobo
E8400 CPU
4x1gb OCZ PC6400 platinum memory
ATI Radeon 4870
XFI Fatality
2x 250gb hard drives raided
DVD burner

The CPU is clocked to 3.6GHz, 1600MHz FSB with 1.3v, I have upped the NB volts one notch and again with the SB, now initialy I was having stability problems untill I changed the ram timings, I noticed on OCZ's site that the memory timings listed for there 4x 1gb kit were slightly lower than that of there 2x 1gb kit that had the same memory, figured that using 4 sticks required lower timings so changed them accordingly and now games and single core folding clients run fine, Also Orthos ran fine for 12 hours.
So I install the new SMP folding client and the machine Blue screens, so I ran Orthos again and it crashed after 15 hours.
So im figuring im on the edge of 100% stability but increasing the CPU volts does nothing.
So could it still be the memory? more volts to the NB? I know 1600MHz is asking a lot of the P35 chipset
If its just the limits of the mobo ill just leave it and not run the Folding SMP client, for everything else its stable, I would just like 100% stabiltiy

[crazyfool]

could be the memory voltage... my rig was unstable before increasing the voltage to 2.1 as this is recommended for my ocz memory... urs might be the same :S

[Platinum]

Got it at 2.1 as it is, might have another mess about with the timings