I purchased 4 GB (2 x 2GB) Mushkin Enhanced BlackLine DDR2 1066 (pc2-8500) 5-5-5-15 from Newegg.com around Christmas. I've tested the memory with Memtest86+ and it gives errors when running the ram at DDR2 1066 (533MHz). It does not give errors when running the ram at DDR2 800 (400MHz). However, my motherboard (ASRock K10N78M) will auto/default the ram to DDR2 533(266MHz), so I have to hard-set the ram in the bios to get it to run at either DDR2 800 or DDR2 1066 speed. I have tried hard-setting the timings, but Memtest86+ doesn't report the hard-set timings. Here is a small table to show the timings and speeds as reported by Memtest86+ for the different DDR2 settings.
As you can see in the above table...Memtest86+ does not report the correct speeds per DDR2 settings according to the Memory Standard Speeds (What it should be running at). Memtest86+ reports the memory as 64-bit, but I'm sure Dual-Channel Memory should be 128-bit, so I'm thinking the motherboard isn't picking up the Dual-Channel Mode, but CPU-Z reports Channel #: DUAL. Also, the timings for the 1066 should be 5-5-5-15 as per product specs.
Another thing that caught my attention is the testing ranges for the memory in Memtest86+.
The first range is 176K - 2048M of 4095M.
The second range is 2048M - 3584M of 4095M.
The third (last) range is 4096M - 4608M of 4095M.
I'm not sure how the 3rd range is even possible and I'm starting to believe that it's the culprit for the BSOD's. I don't know everything there is to know about how memory works, but I'm guessing the BSOD's are moreless an out of range memory error which only happens when more than 3584MB of memory is needed by the system. Is that correct?
Memtest86+ reports errors on the DDR2 1066 only and only when both sticks are in. I've tested each mem stick in both mem slots and neither stick gave errors when operating solo as DDR2 1066.
I've ran Prime95 with the ram set at DDR2 1066 (both sticks)...it fails within 24 seconds every time. When I ran it with DDR2 800...it was stable for 2 hours. I've gotten BSOD's with the 1066 several times during normal operations. I've also gotten 2 BSOD's with the 800, but only when playing Lord of the Rings Online (this is what makes me think it's an out of range memory error).
Also, CPU-Z reports my memory as having a Max Bandwidth of PC2-6400(400MHz)...which is DDR2 800...
All testing was done with CPU Overclocking DISABLED, except for the Prime95 DDR2 800 test which was stable for 2 hours (CPU OC'd @ 3.6GHz and Mem OC'd to 464MHz).
So, can you honestly tell me if my memory is bad? ...or is my motherboard a piece of junk?