Installed new CPU cooler, now only one RAM slot works

[Apoplexy]

Hi, first here are my system specs:
Intel i5 2500K @ stock
EVGA GeForce GTX 460
16 GB Corsair Vengeance RAM
750 W Seasonic PSU - Gold Certified
ASRock Extreme 3 Gen 3 Mobo
Hitachi DESKTAR 7K1000.D 750 GB
Intel 320 Series 120 GB SSD
Lite-On DVD Drive
Windows 7 Home Premium 64-Bit


I recently got help from the Anandtech forum members with a new build that I completed only three days ago. It actually went off without a hitch (initially). I was extremely surprised that there weren't any major problems. The final thing that I had to install was a Corsair H100 cooler. It arrived yesterday and I installed it. But the computer would not POST after the installation. I read a few threads online saying that if you turned your PC on for even a second without the heatsink properly installed (it wasn't getting power when I first tried to run the computer) you would fry your processor. So, I have an RMA in to Newegg for a new processor and I went out and bought a new one today (I'm going to be doing another build later this year with the same processor, so it will all work out.)

Fast forward to today. I get home and install the new processor -- the computer still won't POST. I proceeded to strip the computer down to only the vitals. Still wouldn't POST. I decided to try one stick of RAM in the third RAM slot and it actually booted into BIOS. Unfortunately, when I tried to start Windows it would say "Windows is starting..." and then a BSOD would flash for an instant and the computer would shut off. After some tinkering around in the Windows repair options, nothing was helping so I didn't waste any time formatting my drives (being a new computer, I'm not really losing too much.)

After reinstalling Windows, the computer boots up no problem using the same single channel configuration with one 4 GB stick in the third RAM slot. No other configuration has worked, but I haven't messed around with single channel configurations in only the second or fourth slots. This is where I am now. I can boot into Windows totally fine, I've reinstalled all the drivers and everything seems to be working well, but when I try to use all four RAM slots, or anything except the single stick in the third slot, it won't POST. Did I totally mess up my motherboard while I was installing the H100? I'm really at a loss here. All the memory sticks are fine. I can use any one of the four in the third slot and the computer will run. In the initial install all four sticks were instantly recognized. Any help is greatly appreciated! Thank you in advance.

 

[BoomerD]

Not sure about that particular board, but it's fairly common for a single stick of RAM to be only recognized in certain slots. On my ASUS P7P55D-E Pro board, A1 or B1 (2nd and 4th from the CPU) are the ones to use.
Without knowing the exact motherboard you have, I can't really get a solid answer, but the manual for the Z68 Extreme 3 Gen 3 board doesn't specify which one to use...it only tells which are which for dual channel configs.

I HIGHLY doubt that you fried the processor by turning the PC on with an improperly installed cooler. Usually, in that case, the thermal protection feature kicks in and the CPU shuts the PC off. IMO, it's more likely that either you've damaged a RAM slot, or you have bent pins in the board under the CPU. A last possibility is that your cooler backplate is touching something on the board, maybe causing causing grounding issues.


Best/easiest way to troubleshoot this will be to take everything out of the case so you can eliminate grounding issues. and start with the basics.

First, check the cooler mounts to be sure they're not touching anything on the back of the board.
Next, double check that the fan is connected to the CPU fan header correctly. In fact, check the fan connection BEFORE you dismantle everything...

Then, start with a single stick of RAM in any slot and try to boot. (you should be able to stretch all your case cables to the board...if not, jump the pins for the switch...your PSU cables should be long enough to reach everything.)
If it boots, shut it down and try a second stick of RAM in which ever slot is the dual channel slot mate to the first one. Try again.
If that works, add both other sticks of RAM.
If it boots with all the RAM, reinstall the board in the case and see if it boots. Also, double check the location of all the board stand-offs to be sure one of those isn't causing grounding issues.

 

[Apoplexy]

Thanks for the reply. I've figured out that the computer works fine if I just use the third and fourth RAM slots, but unfortunately this means they can't be in dual channel configuration. Regardless, WEI still gives me a 7.5 for the RAM category, so it's ok. Sounds like this is a fairly common problem with the ASRock Extreme3 Gen3 by looking at the google search results. RMA seems to be the only way people have completely fixed it.

 

[BoomerD]

Yes, ASRock seems to have lots of problems with their boards. I only buy ASUS "premium" boards. I've had nothing but trouble over the years when buying "budget" boards or boards from most other manufacturers. (Yes, I know...many of the others build good boards...I just never seem to get one )

 

[ManBearPig]

Thanks for the reply. I've figured out that the computer works fine if I just use the third and fourth RAM slots, but unfortunately this means they can't be in dual channel configuration. Regardless, WEI still gives me a 7.5 for the RAM category, so it's ok. Sounds like this is a fairly common problem with the ASRock Extreme3 Gen3 by looking at the google search results. RMA seems to be the only way people have completely fixed it.

Odd, when I had my board I used 1/3 and they worked fine.