My setup runs fine with 2x2GB RAM, but I'm unable to get my new build stable with 4x2GB RAM. I've seen similar instances of this question in my Google research. Tried overvolting the CPU and RAM, and manually setting timings at 1600 MHz and 1333 MHz.
Many times mixing RAM even of the same identical part number will not work without issues - if at all. As ncc74656 suggested, slow down the RAM latencies, use T2 and possibly lower frequency, then use Memtest86+ to see if you can find a stable setting. If not I'd replace the RAM with ONE matched, tested 8 GB. RAM Kit designed for your CPU and give the old RAM to somone who might be able to use it.
I had the same problem with my Foxconn A79A-S board and my Phenom II X4 940. My case was with a DDR2 mem controller and RAM but it might be the same for you as well.
Originally I had a 2 stick kit of 2x2GB OCZ RAM. About 8 months or so later I bought another identical kit to run 4x2GB for 8GB total. At first I couldn't run all 4 sticks until I remembered that I changed my RAM to run in Ganged Mode back when I only had 2 sticks. I had to change my RAM to run in Unganged mode to finally be able to run all 4 sticks in dual channel mode. I don't know if the DDR3 mem controller on your CPU has the same issue as mine, but I thought I'd mention just in case.
Nothing, the RAM should run at it's advertised settings. But before we go back there, let me ask a couple of questions that I haven't seen detailed here yet.
1. Are all 4 sticks the same RAM? Do any of the sticks differ from each other in anyway way? I consider a 4 stick kit and 2 identical kits of 2 sticks the same.
2. If they're all the same, did you check if you had Unganged or Ganged mode set for your RAM like I suggested in my post? It was a huge problem for me when I bought 2 identical kits of 2 sticks and ran all 4 sticks together. It would only run in Unganged mode.
Also, the memory controller on your CPU is a 667Mhz controller so it runs DDR3 RAM at 1333Mhz by default. 1600Mhz would be overlcocking. For DDR2 it maxes at 1066Mhz unless overclocked. For now I'd set all settings to default/auto settings and make sure Unganged mode is enabled instead of Ganged mode and try it again.
Ok, you say you can use 2 sticks just fine. Well, divide your RAM into 2 different pairs and make sure you can use both pairs in both the black RAM slots on your board and the blue RAM slots, one pair at a time of course. This way you can make it's not your RAM slots on your board that are causing the problem or that it's just a specific stick of RAM. I haven't seen you state that you've tested both pairs or all 4 sticks individually yet.
This guy was having the same problems you were, except with OCZ RAM, but a moderator posted suggestions for BIOS settings that you might not have tried yet. Of course use the correct timings and voltages for your RAM instead of the ones posted for the OCZ RAM.
Actually, what RAM are you using exactly? Can you post the part number or a link to it by any chance?
You could also try updating the BIOS if you haven't already, if there is an update you haven't applied yet. Of course, I'd only do it with 2 sticks in if there is an update available lol.
Oh, another problem I had a while back, turn off or disable EPP if you have a setting for that in your BIOS settings somewehere.
I came across a post that contained similar information in the OCZ forum. Overvolting got the system to POST whereas it would not before, but it would last 10 minutes or less before crashing.
Also, I installed Starcraft II and it was running fine at first, but then it started crashing sporadically. I changed the RAM timing from 1600 MHz to 1367 MHz in the BIOS, which from what I've read is this processor's preferred memory I/O rate, and no more crashes.
As memory is pretty cheap and it doesn't seem like there's a clear resolution for this issue based on my research, I went ahead and ordered two new G.SKILL 2x4 GB sticks.
I checked out those Newegg reviews, and after learning the AMD processors don't natively support more than one DDR3 1600 DIMM per channel, it led me to G.SKILL forums, which said:
1. Set DRAM Frequency to DDR3-1600
2. Set CPU-NB Frequency to 2400MHz (DDR3-1600 / 2 = 800MHz, then x 3) CPU-NB Frequency should always be 3X DRAM bus frequency
3. Set timings to tCL 9 - tRCD 9 - tRP 9 - tRAS 24, or whatever your memory is rated for.
4. Set DRAM Voltage to 1.50V, or whatever your memory is rated for.
5. Most CPUs will need a CPU-NB Voltage boost of +0.10V, so if your default is 1.10V, set it to 1.20V.__________________________________________________
I did this, but the setup still proved to be unstable. I also noticed through CPU-Z that one of my sets of RAM was physically labeled as F3-12800CL9D-4GBRL, but was actually F3-10666CL9Q-4GBRL. I made sure that I put in two of the former sets and followed the steps from the G.SKILL forums, and it seemed to run Windows fine, but crashed while playing videos in Starcraft II.
Anywho, I got my 2x4GB sticks in, and they're rocking without any CPU overclocking. I think I just passed the 30 day return mark... guess I'll try to Craigslist this other RAM.
Well, that is an odd situation with CPU-Z detecting the RAM as slower than what it's physically labeled. Sorry you had to deal with that and sorry we couldn't figure out a way for everything to work. Give newegg a call anyway and see if there's anything they'll do or make sure you're not past the 30 day mark.
Does your motherboard support quad-channel Ram? If not, isn't using 4 sticks of ram a waste?
It's not a waste, it's just adding more RAM while still maintaining dual-channel mode. Now whether that extra RAM is a waste or not from the simple fact of not ever using as much as RAM as you had before you added more is different. Either way, using RAM in pairs just maintains dual-channel mode whether it's 2 sticks or 4.