P6N Diamond -- running 4x1GB @ 800Mhz

[ts383]

MSI P6N Diamond, with 2 pairs of the Corsair TWIN2X2048 XMS2-6400 memory (4 Gig total).

The memory is listed as 1.9v, 5-5-5-12.

If I install 2 Gigs in either channel, everything is peachy.

If I install 3 Gigs, every thing is as expected.

If I install 4 Gigs, I can't even POST (or access the BIOS). I've gotten the system to boot by lowering the clock down to 710Mhz and increasing voltage to 2.05v, but this is a board that's supposed to handle faster RAM than 800Mhz.

I'm worried of increasing the voltage any higher (although I've got pretty good cooling in place -- I've yet to come anywhere near temperature issues with a Core2Quad Q6600 and dual 512 Geforce 8800s), but surely there's a way to kick this board in the teeth and get the advertised performance?

 

[WazzaUK]

hmm.... i got same mobo/memory (but 4x1gb - unpaired - TWIN2X2048 2x1gb tested pair). No problems with them (5-5-5-12 at 2.0V)...

have you tried EVERY DIMM as one pair or on theyre own? (to rule out faulty memory).

 

[ts383]

Yea, I've swapped out in every combination you can think of.

You say you have 5-5-5-12, as do I, but what's the clock speed of your memory? Do you have it manually set or is the MoBo driving it down to below 800?

 

[WazzaUK]

only thing i've changed is DRAM timings - tRAS: 12 clocks.

CPU core: 3000MHz
Memory bus: 799(DDR2)MHz
FSB: 1332(QDR)MHz

 

[fyffe777]

4 gigs needs 64 bit operating system. Need Bios update 1.3.
- Fixed system report incorrect memory size when install 4G memory. Need to be using XP to used the online update to flash the bios or the old floppy disk method. Once bios was flashed. Bois showed 4 gigs after Vista 64 was loaded

 

[quietfly]

definitely run bios update to 1.3. i know lots of people with the mobo that had similar issues till the bios update.

 

[huron]

Yep...I agree with the BIOS update. I have the board (though I'm switching it out soon) and it was doing the same thing to me with 4x1GB stick of Ballistix until I updated the BIOS.

Hope it works for you.