GA-EP45-UD3R RAM Upgrade Issue

[coder82]

Hi,

I have a GA-EP45-UD3R that originally had 2x1GB sticks of Corsair CM2X1024-6400 RAM (timing is 4-4-4-12), 800MHz, and worked fine. I bought two additional 1GB sticks, but stupidly forgot to get RAM with the same timing. The new RAM timing is 5-5-5-12. Basically, I can mix the original 2 sticks with one of the new sticks and it works fine (3x1GB). However, if I put the 4th stick in, my computer won't POST and powers on for a few seconds and then power cycles itself continually. I've tried manually defining the timing at 5-5-5-12, but that didn't work. Any ideas?

Thanks!

[Lsdmeasap]

Re: GA-EP45-UD3R RAM Upgrade Issue

Mixing memory is always a crapshoot, it might work or might not at all, or it could work and take you weeks of hassling to get it stable.

Try with two sticks installed these settings. Set performance enhance on standard, then set 555-15, then set your ram voltage to 2.1, then set tRD (Static tRead Value) on each channel to 9, and then set MCH Voltage to 1.2-1.24 and then save/apply/reboot F10 to windows. Then shut down and install the second set and see if it will boot or not, if not then you can't mix these sets.

Be sure you are using the latest BIOS as that may help

[coder82]

Re: GA-EP45-UD3R RAM Upgrade Issue

Thanks for the reply. I'm a little familiar with some of the settings you mentioned, so I just wanted to summarize what you said and make sure I'm making the appropriate changes:

-Under standard timing control, change the following:
CAS latency time to 5
tRCD to 5
tRP to 5
tRS to 15

-Under advanced timing control
Change channel A & B tRD to 9

-DRAM voltage to 2.1?

-Which MCH voltage do I change (i.e., core, reference, etc.)?

Thank again.

[Lsdmeasap]

Re: GA-EP45-UD3R RAM Upgrade Issue

Ya, you got all that correct.

Dram voltage I mentioned 2.1V because that's the norm for DDR2 these days, if your kits are rated under that then set the amount they are rated at or a little above.

MCH Core voltage is what I meant, sorry for not specifying.