[Techtalk] adventures with mad RAMS

Carla Schroder carla at bratgrrl.com
Fri Jan 16 05:43:55 UTC 2009

On Thursday January 15 2009 08:08:53 pm Carla Schroder wrote:
> heya,
> I am being foiled by mad RAMs. I have one system that has two DDR2 slots,
> dual-channel. Originally it had just one stick of RAM, and I wanted more so
> I ordered a second one the same size, specs, and brand. There is a nice
> label right on it so I had all the right numbers for matching it. When I
> installed it the system behaved as though there were no memory at all-- it
> powers up, but the keyboard does not light up and the monitor stays black.

Ha! My google-fu is mightier than my hardware-fu. A bit of Web searching 
revealed that resetting the CMOS (short the pins) would re-set the memory 
timings in the BIOS. And lo, I have a working system again. But only with the 
old memory, the new memory is DOA.

According to everything I have read, even on dual-channel boards you should be 
able to mix and match memory (as long as it is within what the board 
supports), and the worst thing that happens is the dual-channel defaults to 
the speed of the slower module.


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