4x2GB ram preventing Overclock

[pirloui]

I have a Gigabyte H55M-UD2P with a i7 860 overclocked to 3.6Ghz (bclk200)

It ran perfectly with 2x2GB 2000Mhz Ram (1.66V)

When I add another pair, it won't pass POST.

Both RAM pairs work individually, just not all together (same speed/timing/voltage...)

It only works if there is no overclock at all. Which isn't an option as I do 3D rendering.

 

Any ideas?

Thanks for reading.

 

Strangely it booted now, after going from bios f9 to f10.

Not a proof of stability yet, but maybe..

[Byrd]

I've seen this happen with Gigabyte boards before - you need to either reset the CMOS straight after installing the new modules, or go into the BIOS before installing new modules, and knock down the RAM CAS settings, and increase the RAM voltage a couple of points.

[pirloui]

It seems it was some settings in the CMOS that weren't appreciated.

The ram voltage had already been set to 1.66V (what the 2Ghz ram specified)

It runs fine now and passes memtest; but I have had a couple of Cinema 4D crashed when rendering for an extended time. Other software stable for now.

Will try to lower / raise the voltage to see if it helps.

Thanks for caring RAM CAS: both pairs do 9-9-9-24, which isn't great; but common at that speed. I doubt it would do it any good to go lower.. Maybe running at 1600Mhz and lowering latency could be worth it..

[craterloads]

going with 4 dims tends to run into trouble when overclocking

 

oops see youve got it sorted