Some memory sticks work in some slots but not in others.

[shorty9]

I have a z87 UD3H gigabyte motherboard with 4 sticks of ADATA DDR3 2GB ram (PN: EL63I1B0823ZV). My computer has been shutting down randomly (No BSoD) and slowing down drastically after about 20 minutes of use. I thought it was a heating problem but after installing a program to check temperatures everything was well within normal ranges. Then after some research online it appears it could be a memory issue. Running memtest was not helpful because it would not complete the computer would crash about halfway in. Also while running memtest it would only recognize that I have 4Gbs of RAM while running the test but the information about the sticks in the program say each stick has 2Gbs. Which is the same thing CPU-Z says. I ran Memory Diagnostic from windows but it came back saying nothing was wrong. I then thought it could be the motherboard so moved the sticks that were in slot 1 and 3 to 2 and 4, but then it would not boot. So I then went through each stick in each slot to see if I could find a faulty stick. But I found that for stick A it would boot in slot 1,2,3 and 4; stick B would boot in slot 2,3 and 4; stick C would only boot in slot 3 and stick D would boot in 2,3 and 4. After I put the stick back into slots in which they would boot and tried running memtest again but again it crashes halfway through. I plan to get some compressed air and clean out some dust because I read that can cause memory failure like problems. I am confused as how to solve my problem I cannot tell if it actually is a memory issue or if it is motherboard issue or how to determine which sticks are faulty.

Thanks in advance.

 

[brispuss]

The problem is likely due to using four 2 GB individual modules which are NOT from the same memory module kit.

Each module has unique characteristics, and in order for modules to work compatibly with each other, the modules characteristics have to be similar. Memory modules in a kit have been tested to ensure compatibility with each other. So it is likely the variance in memory characteristics between the four individual 2 GB memory modules may be too great to allow compatibility between the four modules.

Also, and as observed by testing individual modules in different slots, each memory slot in motherboards also have unique characteristics, and in some cases memory modules may not work (properly) in certain slots due to too big a variance in respective characteristics of the slot and module. So some modules will work (better) in different slots.

If not already done so, clear CMOS, and try the memory again.

If still having system issues then raise DRAM Voltage by 0.05 V. Don't exceed DRAM voltage of 1.65 V, otherwise there is increased risk of memory module failure or shortened module life span.