Win7 64 bits freezes with 2x2GB, but works with 2GB

That is my problem. The freeze occurs randomly (between 5 min and some hours after rebooting), is sudden, everything in the screen is stopped, no BSOD, no event log (except afterwards that detects the unproper shutdown).

I tried dual channel and single channel mode, to no avail.

With 2GB, I have been running for almost a week, no matter which of the two memory sticks I plug in, so apparently both of them are working properly.

The motherboard has 4 DDR2 banks, I have tried almost every combination: A1-A2 (dual channel, reccomended setting), A1-B2 (single), B1-B2 (dual on secondary banks).

My specs are at the left, but most notably it is Kingston memory and the motherboard is ASUS P5KC.

Please help!!!! Thank you in advance!

Hi icalvo & welcome to Windows 7 Forums

As to your RAM you said have you tested your RAM ? Windows 7 has its own RAM test instructions are here > Memory Diagnostics also you may like to try the RAM test from Microsoft here > http://oca.microsoft.com/en/windiag.asp

I would like to ask your Windows 7 installation was this an upgrade or a clean install (and if it was a clean install did you use full format ?)

Veedaz,

Thank you for the reply!

No I've not tested the RAM, I'll do.

It's been a clean install but no full format (there's still the Windows.old of the former OS, Vista 32 bits).

Your Windows old this is a folder ? or have you gone dual boot ?, I was referring to the partition / Drive you installed Windows 7 to (did you use the full format option at setup ?)

Bump up the Vdimm (RAM voltage) a notch or two in the bios. I can tell you more precisely if you give me the exact model number of your RAM modules. You can use the spd tab of CPU-Z.

I didn't choose full format and there is no dual boot, Windows.old is just a backup folder created by the installation.

OK thanks for making that clear, i would test your RAM as RAM can be faulty and still work to a degree.

TorrentG,

I will try the voltage adjustment.

The model is:

KVR800D2N5/2G

Try 1.9v and see how it goes.

OK, I've put both modules, Dual Channel, and set 1.9V.

I've started the Win7 mem test (mdsched) and, about 10% of the first run, it freezed... or almost: it is not really frozen but very very slow. I can go to the Options screen and it shows the screen slowly, from top to bottom.

I left it for a while and it didn't advance.

I exited the test, and it started Windows 7 correctly (apparently the slowness disappeared).

Tried again to see if it froze at the same point, and no, this time it completed sucessfully (and no problems were detected) but Win7 froze afterwards as usual.