GA-EP35C-DS3R: 4x2 GB - can't make it work

[PiotrK]

Hi,

my motherboard is Gigabyte EP35C-DS3R, and I'm trying to add some RAM. My base configuration is 2 x OCZ2T800C44GK, so it's 2x2 GB. I have two more slots for DDR2, so I decided to buy exactly the same "dual kit", just to be sure they'd work together. Unfortunately, after putting them in, Windows freezes during the blue "Welcome" screen, sometimes it manages to show the desktop for a second and then freezes.

I thought the second-hand modules I got are damaged, so I put in only these modules - the computer works just fine, so they seem to be OK.
My CPU and RAM was a bit overclocked, so I restored the default settings - no effect.
I've tried various combinations of modules in the slots, like the new ones in the place of the old ones aso. - no success.
I've also run a couple of tests in memtest and Windows Memory Diagnostics, and they show no error!
It's not old BIOS' fault, I've just updated it.

Does anyone have an idea what may be wrong with my motherboard?

[PiotrK]

Problem solved.
The reason was the default memory frequency multiplier. I've just noticed this option in BIOS - System Memory Multiplier. The motherboard was setting it too low by default, so that the memory frequency was around 500 MHz. My modules require at least 800 MHz, so it was just a matter of setting the multiplier to 2.0 (in my case) instead of Auto.