Greets! I recently built a new sandybridge PC for a friend and here are the specs:
Intel Core i5 2500K
GIGABYTE GA-Z68MA-D2H-B3 http://www.newegg.com/Product/Product.aspx?Item=N82E16813128495&cm_re=z68_gigabyte-_-13-128-495-_-Product
Memory: GSkill Sniper 8gb http://www.newegg.com/Product/Product.aspx?Item=N82E16820231460&Tpk=sniper%208gb
EVGA GTX460 1gb SC
After installing windows 7 (which installed fine), I ran memtest86 just to see if there are no errors with the RAM. I used a linux mint live cd which comes with a memory test and to my surprise, the memtest that came with that distro doesn't even run - it crashes right away. So I went and downloaded the latest versions of memtest from memtest86.com (versions 4.0 date released 28-March-2011) and memtest.org (memtest+ version 4.2 25-January-2011) burned the ISOs to disk.
The first thing I noticed is that memtest+ 4.2 doesn't detect the RAM settings correctly - It thinks that I have Triple Channel and CAS of 6-6-6-20 - but its supposed to be DUAL channel and CAS 9-10-9-28. On the other hand, memtest (not with +) detects my i5 as an i7 and has "unknown" caches.
Unfortunately, both memtest and memtest+ gave errors on my Sniper modules. So I ran one stick at a time to see which of the two dimms are causing the problem (memtest86+ detectes as Single Channel but still CAS 6-6-6-20 instead of 9-10-9-28)
Things are so weird with my results and for better understanding I will name my two x 4gb Sniper modules A and B.
Here are the results:XMP enabled running at 1866mhz
memtest 4.0 = both DIMMS gave errors (after 2 passes)
memtest+ 4.2 = DIMM A had no errors // DIMM B had multiple errorsXMP Disabled running at 1600mhz
memtest 4.0 = DIMM B had no errors // DIMM A had some errors -- (WTH! the exact opposite of the XMP enabled 1866 memtest+ test)
memtest+ 4.2 = both does NOT
have any errors (2 passes) --> this is the only time no errors were reported in all my tests.
I tried different DIMM slots just to be sure (all slots gives errors - 2 passes each slot).
As you can tell, all tests have very mixed results and I'm starting to believe that memtest/memtest+ could not just utilize the Z68 chipset yet.
The next thing I did made it a lot weirder. I used my own PC and swap parts with my friends PC. My motherboard is a MSI P55-GD86 and I use G.Skill Ripjaws 4 x 2gb DIMMS 1600Mhz. At first, I tried using the Sniper on my P55 board and memtest+ detected DUAL Channel and CAS properly. With my P55 board, there were no errors at all - XMP enabled/disabled. On the other hand, memtest (not with the +) failed to even run on my P55 board - I wonder why.
I placed my Ripjaws to the Z68 board and ran with XMP enabled and disabled. Both didn't give any errors.
Just to make sure it is not the Power Supply, I swapped MY Corsair TX650W with his CX600 - its not a power supply issue.
I didn't do any voltage changes on the DIMMS or anything as I haven't done anything like that before. I just know that the Sniper is rated and running on 1.5V on the Z68.
BTW, I'm not having crashes on Windows 7 and CPU-Z detectes CAS properly inside windows. Everything is actually fast inside windows.
Could it be the motherboard that is faulty? The Dimms? Memtest/Memtest+ error? Just needs a voltage bump? or nothing is faulty?
Is there any other memtest-like test that I can use just to be sure that the DIMMS are good? Within Windows 7 would be nice.
PS: If I need a voltage increase, could someone please teach me how to do it? What voltage increase is safe? I'm currently running at 1.5 right now.