BleepingComputer.com: dual channel memory freeze

Hello,
I posted this in another topic but have not gotten any responses, so I will put it in its own topic for a higher probability.
I have been having computer freeze issues and have narrowed my search to the memory.
I have (2) dual channel 3200 512mb sticks in the proper slots. There are 4 slots on the mobo (Asus P4P800 - E delux)
I have run memtest from a floppy disk as recommened by the makers of memetest.

Anyway at the LRAND portion, the test freezes and the only way out is by a hard stop. I have taken out the sticks and reversed them slot 3 to slot 1, test freeze again. Them moved the sticks to 2 and 4, test froze again. I reversed the sticks from 4 to 2 another freeze.
The last thing I have done is to test each stick individually in single channel mode and the test ran for hours on each stick in each of the 4 slots. no problems

My questions are this:
1) Is the dual channel portion of the mobo fried?
2) Is it possible the the sticks will no longer work together in dual channel mode? but work independantly?

By the way I am now running the computer with one stick of 512 single channel mode and have not had a freeze up yet. Where as before I would get a freeze 4-5 times a day.


Thank you for any responses
Bob

Bob,

Try re-running memtest86+ on each stick of ram independently. This should help you narrow down which stick of ram is defective. You can then contact the manufacturer or place of purchase for replacement.

Hope this helps,

IMO (I'm certainly no expert)...if the RAM modules are not matched (all the same), there is a chance that timing differences exist which interfere with them all running together.

I had a situation like this earlier this year. I looked at the Memtest results and then fiddled around with the modules until I verified that the timing differences were the key factor. Once that was done, I then went into the BIOS and downclocked the FSB...to see if that would enable compatibility between the different modules (I went from 200 to 166).

When I rebooted with all of the mods in place, the problems had all gone away.

What I learned: Just because the RAM module says that it runs at a given speed...that doesn't make it compatible with different RAM modules of the same stated speed.

Louis

Second previous suggestion re Memtest 86+. Memtest86+ - Advanced Memory Diagnostic Tool - http://www.memtest.org/#downiso AND Icrontic » Diagnose with Memtest86+ - http://icrontic.com/articles/diagnose_with_memtest86

This post has been edited by hamluis: 18 June 2009 - 10:29 AM

Like hamluis said, the problem could be that your FSB is running faster than the RAM itself, which often causes freezing because the RAM isn't acting fast enough.

However it could also be defective RAM. Memtest should clear that up and we can go from there.

-mhr+

thank you all for the responses.
Both sticks were bought as a 1gb set.
I will try the memtest86+ and see what happens, however as stated earlier each stick has no errors when tested individually in each of the 4 slots on the mobo. It is only when I put both sticks in together as dual channel that the test freezes and I have to do a hard shut down.
Bob

I've been thinking about this one for quite awhile and have looked at the "DDR 400 QVL for ASUS P4P800-E Deluxe Motherboard" pdf file located at http://dlcdnet.asus.com/pub/ASUS/mb/sock47..._Deluxe_QVL.pdf

My suggestion would be to check your memory against what is on this list and see if it is there. As everyone else was saying I think I would also try lowering your memory speed and see if that helps.

Good Luck,

OK here are my test results from the memtest86+
single channel mode
stick #1
slot 1= pass, 0 errors
slot 2=pass, 0 errors
slot 3=pass,0 errors
slot 4= pass, 0 errors

stick #2
slot 1= pass, 0 errors
slot 2=pass, 0 errors
slot 3=pass,0 errors
slot 4= pass, 0 errors

Dual channel mode
stick 1
slot 1
stick 2
slot 3
On test #5 the computer froze and I had to hard shut down

stick 1
slot 2
stick 2
slot 4
On test #5 the computer froze and I had to hard shut down

It seems like the memory will work as single channel, but not in dual channel. My assumptions would be the motherboard no longer works in dual channel mode.

Any thoughts?
Bob

If it's not the RAM sticks...it's your FSB/motherboard that falls in line as the next suspect, IMO.

I've already convered what I see as options there.

Louis

You mightn't be in a position to do it, but being able to test the memory in another system, and alternative memory in that board could be the best way to be sure whether it's the memory, the board or just the combination of that memory in that board.