Problem with A7N8X Deluxe rev2, CMX256A-3200LL, and VS512MB400

[jykno]

Hi everyone,

 

I have been using the combination of CMX256A-3200LL (@200MHz, dual-channel) on an A7N8X Deluxe rev2 successfully for quite some time now. Thinking of upgrading to 1GB, I added a stick of VS512MB400 to the mix, thinking that the two will work (even if defaulting to a slower CL rating). Unfortunately, not only this combination does NOT work, trying to revert back to just using the CMX no longer works :(

 

Memtest shows that the original CMX pair tested fine, as well as the VS on its own. Using all at once (tried different combinations of memory slots) shows a (rather large) number of errors.

 

After this disastrous "experiment", using either the CMX pair on its own, or the VS on its own causes Windows 2000 (Pro) to lock up during the graphical boot up screen (the screen is also corrupted). The system also runs Linux, and starting X-windows will now locks up (blank screen). On the other hand, Linux' console (text) mode seems fine, as well as performing compilation. Changing memory speed and timing in BIOS doesn't seem to help (timing changes will sometime cause failure to POST). Upgraded to the latest BIOS (1008D), also to no avail.

 

Given that memtest doesn't show errors on testing the CMX and the VS modules separately, does this point to the motherboard being damaged in any way due to trying to use both modules? Any suggestions on what to try next?

 

Thank you for your time, any help would be appreciated.

P.S. My apologies if this post doesn't show correctly, as I'm typing this on a text-based browser, due to the problem above :(

[Jabberwok]

After upgrading your BIOS did you reset CMOS & load setup defaults?

[jykno]

After upgrading your BIOS did you reset

CMOS & load setup defaults?

Thanks for the reply.

 

I believe at the time I reflashed the BIOS, it did went to default settings, and still didn't work. To verify, I've just tried going back to the default settings again, and it won't even POST.

 

I'm running an Athlon XP2500 setup with no overclocking whatsoever. In the default setting, the MB clock speed is set to 100MHz, which I need to manually set to 166MHz. In the case of the memory timing, it was set to [Auto] (2T-2-2-5) using the CMX pair, which won't POST at all. Changing this to [sPD] (2T-2-2-6) will get it to POST, but still won't allow Windows (and X Windows) to start :(

 

I've also tried increasing the reference voltage to the DIMM to 2.7V (from 2.6V) with no effect at all. Is it possible that having both CMX pair and the VS somehow 'damages' the MB at all?

 

Any help would be appreciated.

[RAM GUY]

I am sorry but you should not mix modules especially with a dual channel MB.

I would suggest you use Twinx1024-2700LL if you have a 133/166 FSB CPU or Twinx1024-3200XL if you have a 200 FSB CPU for best performance. Other wise you would need to get a module that is the same part# and revision as what you had.

[jykno]

Many thanks for the advice. I think I've learned my lesson on the risks on mixing modules. Luckily in my case, the problem seems to have resolved itself, so it looks like it's neither the memory sticks nor the MB, most likely dust or contact issue :o:

 

All three sticks seems fine now, running at 3T-3-3-8.

 

RAM GUY:

I am sorry but you should not mix modules especially with a dual channel MB.

I would suggest you use Twinx1024-2700LL if you have a 133/166 FSB CPU or Twinx1024-3200XL if you have a 200 FSB CPU for best performance. Other wise you would need to get a module that is the same part# and revision as what you had.

 

Ram Guy, out of curiosity, are CMX/TwinX pairs meant to be used on their own, and not to be combined with a VS (for example), or other CMX/TwinX pairs (in a 4 slot MB)? Or do you mean there is a VS out there somewhere with the same part # and revision as my CMX pair which should be more 'compatible'?

 

Thanks!

[RAM GUY]

You should not mix memory VS and CMX or any other modules. All modules should be the same part# and revision.