Bad memory or bad motherboard? Help!

[ExPA]

Hi!

My system:

Custom built
Intel Bad Axe 2 motherboard
Intel Core 2 Duo E6600
Corsair 520 PSU
Corsair Value Select 2x1GB 667
eVGA 7950GT graphics card
NEC 90GX2 monitor
3- Seagate Barracuda 7200.10 320GB HDDs
Lite-On SATA DVD-ROM
Lite-On SATA DVD R/W
Antec 900 case
MS XP Pro SP2

My problem:

System ran fine with initial pair of RAM modules (2-1GB) for total 2GB memory.

Installed a second set of identical modules to boost to 4GB memory. System started crashing.

Ran Windows Memory Diagnostic and memory failed LRAND and WMATS+ tests on every one of multiple passes.

Swapped the two pairs of modules between DIMM0 and DIMM1 (i.e., kept all 4 modules in for 4GB total memory). Ran Memory Diagnostic and system passed. Fewer crashes, but still occasional crashes.

Never had BSODs with crashes... only to desktop.

System started crashing frequently again. Ran Memory Diagnostic and LRAND and WMATS+ failures again appeared.

Here's where it gets weird...

Pulled out modules from DIMM1 and ran Memory Test. Pair remaining in DIMM0 passed all tests on multiple passes.

Swapped the module pair I pulled from DIMM1 into DIMM0 and ran Memory Test again (i.e., only one pair in for total 2GB memory). The second pair of modules also passed all tests on multiple passes.

So it seems the memory problems are only occurring when I have both DIMM0 and DIMM1 populated.

Is the problem with the DIMM1 slots of the motherboard rather than the RAM modules?

Any help greatly appreciated!!!

ExPA

[LeftyAce]

I had similar problems when I went from 2 DIMMS to 4, and the solution was to put the ram on a divider. Find where your memory speed settings are in your BIOS and turn the ram down one step from where it is, and see if that solves your problem. (The setting may be tricky to find; mine was under 'cpu settings' of all places! )

[chuck4456]

There was a BIOS that addressed that problem.
May just need an updated version.
Check out INTEL i975x Tools and Updates.

[ExPA]

Originally Posted by chuck4456 There was a BIOS that addressed that problem. May just need an updated version. Check out INTEL i975x Tools and Updates.

Thanks for the message. I actually already have the latest BIOS update installed (June 13, 2007), and I didn't find anything else around the Intel support site that acknowledged a specific problem with memory when populated all 4 DIMM slots. But I'll keep checking since I may have missed something. cheers...

[ExPA]

Originally Posted by LeftyAce I had similar problems when I went from 2 DIMMS to 4, and the solution was to put the ram on a divider. Find where your memory speed settings are in your BIOS and turn the ram down one step from where it is, and see if that solves your problem. (The setting may be tricky to find; mine was under 'cpu settings' of all places! )

Hi LeftyAce... Thanks for the message.

I found where the memory speed settings can be adjusted both in the BIOS and in the Intel Desktop Control Center. Only option is to change from 667MHz to 533MHz. Is that what you meant by changing the speed? If so, I'm wondering if that will make my RAM slower than the system bus (or whatever that other bottleneck was that I remember reading about somewhere) so that my system would slow down, rendering the RAM capacity increase a net detriment to system performance (i.e., RAM slowdown more than offsets gain from raising RAM from 2GB to 4GB capacity).

Any suggestions or other thoughts?

Thanks! ExPA

[LeftyAce]

That option of 667 or 533 is what I was referring to. Are there no options in between?
If you're going to change speeds, I'd do it in the BIOS rather than the desktop utility.

If you use close to 4GB of ram regularly, the larger capacity will definitely outweigh the speed decrease.

Otherwise, your processor is actually running a front side bus of 533, so ram at 533 is running 1:1, so you *shouldn't* take a performance hit. For some reason the C2Ds are happier with a little overhead, but I think you'll be fine at 533. If it's painfully slow, then I was wrong :-)

My main area of experience is with the AMD Athlon64 processors which were actually ok to run a little below 1:1 (so I was running a 200MHz FSB and my ram was at 183). Not sure whether the new Intels are that flexible though.

[ITlover]

Originally Posted by ExPA Hi! My system: Custom built Intel Bad Axe 2 motherboard Intel Core 2 Duo E6600 Corsair 520 PSU Corsair Value Select 2x1GB 667 eVGA 7950GT graphics card NEC 90GX2 monitor 3- Seagate Barracuda 7200.10 320GB HDDs Lite-On SATA DVD-ROM Lite-On SATA DVD R/W Antec 900 case MS XP Pro SP2 My problem: System ran fine with initial pair of RAM modules (2-1GB) for total 2GB memory. Installed a second set of identical modules to boost to 4GB memory. System started crashing. Ran Windows Memory Diagnostic and memory failed LRAND and WMATS+ tests on every one of multiple passes. Swapped the two pairs of modules between DIMM0 and DIMM1 (i.e., kept all 4 modules in for 4GB total memory). Ran Memory Diagnostic and system passed. Fewer crashes, but still occasional crashes. Never had BSODs with crashes... only to desktop. System started crashing frequently again. Ran Memory Diagnostic and LRAND and WMATS+ failures again appeared. Here's where it gets weird... Pulled out modules from DIMM1 and ran Memory Test. Pair remaining in DIMM0 passed all tests on multiple passes. Swapped the module pair I pulled from DIMM1 into DIMM0 and ran Memory Test again (i.e., only one pair in for total 2GB memory). The second pair of modules also passed all tests on multiple passes. So it seems the memory problems are only occurring when I have both DIMM0 and DIMM1 populated. Is the problem with the DIMM1 slots of the motherboard rather than the RAM modules? Any help greatly appreciated!!! ExPA

If these DIMM are working fine on other computers than there is nothing wrong with them, then the problem definitely lies on your motherbaord.

[perkster]

i hope its 64 bit version of XP pro you have or you wont really get benefit of the 4gb ram anyway.

[ExPA]

Originally Posted by LeftyAce That option of 667 or 533 is what I was referring to. Are there no options in between? If you're going to change speeds, I'd do it in the BIOS rather than the desktop utility. If you use close to 4GB of ram regularly, the larger capacity will definitely outweigh the speed decrease. Otherwise, your processor is actually running a front side bus of 533, so ram at 533 is running 1:1, so you *shouldn't* take a performance hit. For some reason the C2Ds are happier with a little overhead, but I think you'll be fine at 533. If it's painfully slow, then I was wrong :-) My main area of experience is with the AMD Athlon64 processors which were actually ok to run a little below 1:1 (so I was running a 200MHz FSB and my ram was at 183). Not sure whether the new Intels are that flexible though.

Thanks for all the additional info and advice LeftyAce! I'll toss the modules back into DIMM1, give 533 a shot from the BIOS, and see what happens. (And no, there were no options between 667 and 533). I can probably try clocking some high memory use 3D renders to see if the capacity vs speed trade-off is right for my needs. With only 2GB installed, some of my 3D scenes close a render and then post an error that there isn't enough memory to reload the textures. It'll be interesting to see if the higher capacity stops those errors. I'd certainly be willing to take a little rendering speed hit to avoid having to close the app and reload the file after each render.

Originally Posted by ITlover If these DIMM are working fine on other computers than there is nothing wrong with them, then the problem definitely lies on your motherbaord.

Thanks for the message, ITlover. I didn't try the modules in a different computer. I just mounted each pair in DIMM0 on the machine in question, then ran the memtest. I figured if each pair passed in DIMM0 there shouldn't be a problem with the modules. So I'm thinking you may be right about DIMM1 in any case... or it could be some other problem like the OS choking on the memory it can't use (i.e., Win XP Pro seems not to recognize more than 3.25GB of the 4GB installed RAM... but I'm talking out of my knowledge league here).

Originally Posted by perkster i hope its 64 bit version of XP pro you have or you wont really get benefit of the 4gb ram anyway.

I had thought about the 64-bit version when I built the thing this past Spring, but it seemed many people were concerned about poor or nonexistent drivers. I opted for the 32-bit XP. It does seem to register only 3.25GB memory in the system info, so I think you're right that I'm not getting the full benefit.

When I got the 32-bit XP OEM from newegg, an "upgrade" to Vista business version was included for free. I have the disk sitting on a shelf and was thinking I might install it some day in a dual boot setup. If I remember right (something which doesn't happen as often as it used to), this version of Vista would access the full 4GB. If so, I might give it a try.


Thanks again to all for thoughtful replies!