a bad chip?

[doubleaught121]

I purchased this ram a while ago (from zipzoomfly when it was googlegear iirc), and have suspected problems with it but didn't have anything firm until now. The chip is a 512MB PC2700 xms part, here's the info off the part itself:

 

CMX512-2700C2

XMS2702V1.1

024623

 

Though there is more information available to indicate problems, I will narrow in on the more "incriminating" bits:

- when I put this ram into an asus a7n8x (v2.0, latest bios) and let it auto detect by spd, the computer will not boot, just giving long repeating beeps. I can boot just fine with another xms module, manually relax timings and force 166mhz and it's works okay then (and only then).

 

- I recently purchased another 512mb pc3200 and gave the offending pc2700 chip to my dad, his computer did the exact same thing with this chip (long repeating beeps), yet works perfectly fine with it's own value pc2700 256MB chip and also a corsair 512MB value chip I borrowed from my gf's pc to test with. This time though, no matter what I do his computer will not boot with a 133mhz fsb with this chip installed - without it, no problem at all. If I force timings to relax AND underclock the machine to 110mhz fsb (which since I can't lock the ratio it OCs the pci bus, something I'm not comfortable doing) it will boot at this (undesired, slower) speed.

 

 

Personally I would really rather not run more tests as I feel there is enough evidence here to "convict", but if there is absolutely no avoiding it I can run more tests.

 

Thanks for your help!

:D

[RAM GUY]

Please make sure that you have the latest BIOS for your MB and load Setup/Optimized default settings, and try the following BIOS settings;

TwinX1024 or TwinX512-3200C2

CPU Freq: 166 MHz (333 FSB)

System Performance: User Define

Memory Frequency: 100%

Resulting Frequency: 166 MHz (333 FSB)

Memory Timing: User Define

SDRAM CAS Latency: 2.5T

SDRAM RAS to CAS Delay (tRCD): 3T

SDRAM Row Precharge (tRP): 3T

SDRAM Active to Precharge Delay (tRAS): 6T

DDR Reference Voltage: 2.7 Volts

AGP Voltage: Default *unless you have ATI (9200 or 9600) or NVIDIA (5200 or 5700) then 1.6 Volts suggested!*

All other settings are motherboards defaults

Then please test them one at a time with http://www.memtest.org and let’s make sure it's not some other issue! I would run the test for at least 2-3 passes to be sure!

[doubleaught121]

hmmm, I already stated I have the latest bios in the machine running with a 166fsb?

 

devil's advocate bit: If all I had were this faulty chip (and no other ram at my disposal), I could not boot into bios at all, so how could I change bios settings then?

 

 

You suggest overvolting the ram to get it to work, imho I shouldn't have to crank the volts (yes even by .1v) to get something to work that should already be working at default/stock settings. I bought the top of the line corsair xms brand (partly) for reliability, so while I can 100% agree with the need to qualify returns, I believe there to be enough circumstantial evidence here to point to a bad module. Why else would it not boot at even 133mhz when another 512MB pc2700 corsair module does so with no problems? (maybe lower spd timings are detected and the motherboard is incompatible with them - no, because I can use other chips to manually set more relaxed timings and it won't even boot at 133mhz in that MB.)

 

It's a significant inconvenience to do more testing. If my logic is flawed and it is explained to me why I'm wrong, I will most definitely apologize and run all the tests you need. Otherwise I'd love to have an RMA #.

 

Thanks!

[RAM GUY]

Please follow the link in my signature “I think I have a bad part!” and we will be happy to replace them or it!