Half of RAM gone after crash/power reset

[#1RAGE]

I rarely put my desktop into sleep mode but I did the other day and when I went to go wake it up the computer was running, fans on, monitor in standby. No matter what I did, the monitor stayed in standby. Even the reset and power buttons wouldn't reset or power it down, including holding power for 10 seconds. I had to kill it with the switch on the PSU. When I powered it back up I noticed it said I had 8192 MB of memory which is not correct since I have 16,384 MB normally and have not ever changed my RAM configuration. I have 4x4GB installed. Looking in the UEFI it shows 8192 MB installed but there is a section where I can select each DIMM and all show XMP profiles and values. In Windows running CPU-Z I can see all four DIMMs yet Windows only see 8GB. I cleared the CMOS and even re-flashed the UEFI/BIOS and it didn't change anything

I spent some time last night removing the sticks of RAM and installing them one at a time and saw some really odd things. When I populated the first DIMM (A1) I got a RAM configuration error, possibly because it needs two DIMMs for dual channel. Then I installed the second stick into B1 (A1+B1 for 2 sticks is proper according to manual) and it showed 8192 MB in the DIMMs I was using, good. Then I put the other two sticks in A2 and B2 (A1 & B1 still installed) and when I booted it showed 8192 MB but only the sticks in A2 and B2. I noticed after several boots it seems to choose either the A1/B1 pair or A2/B2 pair but never all four like it used to, and it seems fairly random.

Is my motherboard smoked or does it seem like there is a problem with one or more memory sticks?

System specs:
ASRock Z77 OC Formula (2.30 firmware)
G.Skill F3-14900CL9-4GBZL (4GB x 4)
Intel i5 3570K (was running @ 4.6 GHz but now at stock for troubleshooting)
Windows 10 Home 64-bit

I definitely have some more troubleshooting to do but I was hoping to get some feedback and experience from everyone on this problem.

I was thinking of upgrading to a 6700K but had recently convinced myself I should save some money and hold off. Now thinking I may have to go back to the upgrade plan.

TL;DR
UEFI and Windows show 8GB of 16 GB installed. All sticks can be seen in UEFI and CPU-Z but only half actually usable. Happened after powered off while locked up in sleep.

Any help/suggestions are welcome. Thanks!

 

[Puffnstuff]

Using one stick at a time run memtest. If a slot is not registering then it probably has failed and if the board is not under warranty you will have to replace it. The other thing is to leave it unplugged without any power (including the cmos battery) for a few minutes to completely deenergize the hardware and then see if the problem persists. Memory slots should work regardless of how many slots are populated.

 

[LTC8K6]

^That^

 

[cyclohexane]

My guess would be a Windows issue. Try system restore?

 

[jihe]

I have something very similar on my P8Z68. In BIOS and CPU-Z all ram sticks were detected in their slots but only half of them were usable. Another thing was IGP did not work anymore. Have you tried the IGP? Took me ages to find out it was due to the Intel ME region of BIOS being corrupted. Note that a normal BIOS reflash will not fix this. I fixed it using FTK version 8 (had to try all the versions until the right one worked):

http://hardforum.com/showthread.php?t=1726429

 

[#1RAGE]

It has been a busy past couple of days but I did a little more testing.

Using one stick at a time run memtest. If a slot is not registering then it probably has failed and if the board is not under warranty you will have to replace it. The other thing is to leave it unplugged without any power (including the cmos battery) for a few minutes to completely deenergize the hardware and then see if the problem persists. Memory slots should work regardless of how many slots are populated.

I tried the removing power and CMOS battery first but that didn't change anything.

Next I removed all the sticks of RAM and numbered them 1 through 4. I put Stick 1 into slot A1 ran memtest and passed. Then removed stick 1, and put stick 2 into B1 and ran memtest... and so on. So basically I ran each stick in a different slot and each one passed. Then I did pairs as recommended for dual channel configurations and both pairs passed. Then I put all four sticks in and the same problem as before, meaning only one pair would work.

I have something very similar on my P8Z68. In BIOS and CPU-Z all ram sticks were detected in their slots but only half of them were usable. Another thing was IGP did not work anymore. Have you tried the IGP? Took me ages to find out it was due to the Intel ME region of BIOS being corrupted. Note that a normal BIOS reflash will not fix this. I fixed it using FTK version 8 (had to try all the versions until the right one worked):

http://hardforum.com/showthread.php?t=1726429

Interesting... I'm not sure about the IGP because I have never used it. I will try it. I'll also take some time to look at that thread but that looks like quite the process!

 

[Puffnstuff]

I would take a stick that you know works and try it in each of the slots. I had a similar issue not so long ago with an x58 board and I had a bad slot. The only way to know for sure was to move a single working stick around all of the slots taking note of which ones did not register it.

 

[#1RAGE]

I would take a stick that you know works and try it in each of the slots. I had a similar issue not so long ago with an x58 board and I had a bad slot. The only way to know for sure was to move a single working stick around all of the slots taking note of which ones did not register it.

I think what I did covers that. Instead of moving a single stick around I just assigned each stick to a slot but tested them individually and all sticks/slots passed. The problem isn't that I'm getting memory errors, it is that the motherboard is choosing not to use all four at the same time or it is having trouble seeing one of the pairs.

 

[#1RAGE]

I decided to just go with 8 GB of RAM for a while so I was about to overclock my CPU again when I noticed a bunch of UEFI settings are now gone. D: After some googling I found this thread where the OP has the exact same problem (items missing from UEFI). http://www.tomshardware.com/answers/id-1786727/asrock-formula-bios-xmp-problem.html

Ugh! Going to try flashing older firmware and do some other messing around later this week but it's really starting to look like upgrade time.