Quad Channel Issues - Memory Controller?

Hello everyone!

1.5 years ago I built my current system using an Asus Rampage IV Formula, 4 dimms of Corsair Vengeance (CMZ16GX3M4X1866C9), with an Intel 3930k CPU overclocked at 4.5Ghz.

The system ran smoothly for over a year, but recently programs begun crashing randomly and then I was getting a lot of BSODs, 3 or 4 per day.

First I updated all the drivers (graphics, audio, peripherals and Windows itself), ran some antivirus tests, I uninstalled some programs, updated the BIOS, down-clocked my CPU and even ran some benchmarks to make sure the system was stable and the software was fine but the problem persists. So I took the whole system apart, cleaned each component and assembled it again... no luck, the system kept crashing.

So I decided to test my ram with memtest86 and it showed a ton of errors with the 4 modules installed. Then I tested each module individually and each slot on the motherboard, no errors found.

Right now I am using just 3 modules and everything runs fine again without errors, but when I install the fourth dimm again, it shows a lot of errors on memtest and the system crashes.

I never overclocked my ram and I am constantly monitoring all temperatures and voltages on my system, the highest core temp under 100% load @4.5Ghz is 63°C.

Another thing is that my ram is running @1866Mhz at 1.5v but my CPU supports up to 1600Mhz, is that a problem?

It seems that my system doesn't like having the ram in quad channel configuration anymore.

Is it possible that there is a problem with the memory controller itself?

Any suggestions?

Thanks!

I think for now we should assume the IMC is fine as a fault on one of the channels would affect two sticks of RAM, not just the one.

Try running all 4 at default bios settings. If you still get failures try upping the ram voltage to 1.55V. How does it run in dual channel mode?

1866, being the rated speed of the ram, cannot be guaranteed on all processors and motherboards. As you've already pointed out your cpu supports up to 1600. Perhaps running @1866 for all this time has degraded either the RAM itself or the IMC, only to the extent a little more voltage is needed.

Worst case scenario - the RAM may be getting a little tired and possibly heading towards complete failure of either the stick that's giving problems or the IMC itself.

I think for now we should assume the IMC is fine as a fault on one of the channels would affect two sticks of RAM, not just the one.

 

Try running all 4 at default bios settings. If you still get failures try upping the ram voltage to 1.55V. How does it run in dual channel mode?

 

1866, being the rated speed of the ram, cannot be guaranteed on all processors and motherboards. As you've already pointed out your cpu supports up to 1600. Perhaps running @1866 for all this time has degraded either the RAM itself or the IMC, only to the extent a little more voltage is needed.

 

Worst case scenario - the RAM may be getting a little tired and possibly heading towards complete failure of either the stick that's giving problems or the IMC itself.

Thanks for your help Ripshod!

This mobo only has 4 slots, one for each channel. I tested all the slots in single channel, dual channel and triple channel configurations without any issues. The slots seem to be fine and also the dimms seem to be fine, the problem happens only when I populate all 4 slots in quad channel configuration.

I will try the bios default settings and also increasing the ram voltage a little.

If that doesn't work, is it possible that the IMC is damaged?

If that doesn't work, is it possible that the IMC is damaged?

It's always possible, tho the least likely until we rule out anything else. tbh in my days I've never come across an intel with a damaged IMC personally, plenty of AMDs tho. I have a 1090T with a blown IMC, makes a nice paperweight.

It's always possible, tho the least likely until we rule out anything else. tbh in my days I've never come across an intel with a damaged IMC personally, plenty of AMDs tho. I have a 1090T with a blown IMC, makes a nice paperweight.

I installed the fourth dimm back again, and ran memtest86 again at 1.55vols, same problem. Then I used the default Bios setting, no luck. Finally I lowered the ram to 1600Mhz and the problem persists.

So I assume that the IMC is indeed damaged.

I already ordered a new 4930k, keeping my fingers crossed!