e6750 overclock need advice

hey guys, i'm using E6750 on Gigabyte p35 ds3l + 2x 1gb crucial ballistix 6400.

currently CPU @ 462mhzx8= 3.7ghz, 1,43V, 60deg on load.
ram @ 924mhz, 5 4 4 12 timings, 2.2V

this settings has been running prime95 passed 24hours stable.

i'm trying to push to 3.8ghz or higher but always fail prime95, even though it passes superpi.

how do i know if it's the rams that's limiting core speed or the cpu hitting fsb wall?

ballistix should be able to go further than 950, with better timings than 5 4 4 12 right? but when i try the exact same settings with 4 4 4 12 , it fails prime95.

need some advice on temps too. gonna have to keep this rig for 2-3 years so is <70degrees safe on max load or must it be <60?

For me, if I set the ram freq high and doesn't post, I figure it's the limit

I know it's a bit stupid to ask but, did you raise the voltage for the cpu? The motherboard? The ram?

If so, then follow the advice by cnumartyr

I think it's time to start messing with PLLs, VTT (FSB Termination), and GTL Refs if you want to climb any higher.

Short answer? There really isn't one.

Basically it's stuff that can assist in reaching a higher stable bus speed.

If you've dropped the CPU Multiplier and can't get 465 stable, it's time to start bumping up the CPU PLL, GTL Ref, and CPU VTT. My suggestion would be finding information on those and reading up on them.