[SOLVED] PC wont boot with oc Ram

[Ciprian.ss]

Hi,

History:
I have a asus Z mother board bought about 5 yrs ago with 4x 4gb ddr4 HyperX 2666mhz.

The Issue:
The rams are clocked at 800mhz when they came out of the box, but can be overclocked at 2666mhz which I did in BIOS and it worked, but sometimes for no reason (actually there might be one, when I move or knock the pc unit) my pc wont boot, it happens since I bought the pc about 5yrs ago.

My method of fixing:
I've used the same method to fix it all these years which I found it by myself, i'm no pc nerd but I'm an engineer and know some stuff about pc's aswell.
Step1. Remove 3 ram units and leave only one
Step2. Start the pc and it works, it boots with only 1 ram installed
Step3. Enter in BIOS and set to default the whole overclock settings, then reboot
Step4. Install 1 by 1 the rams until they boot all 4 togheter
Step5. Go in BIOS and do the overclock again
Step6. Boot and it works
Step7. When I knock the pc and doesn't boot agai, i'll go to step 1 and redo it again

Conclusion:
My guess is that when I knock the pc one of the ram is moved and not connected properly into the slot and gets to default setting of 800mhz while the other 3 are at 2666mhz and my pc has 2 different values for the ram and wont boot. By removing 3 and leave only 1 there is only one value in the ram unit which is 2666mhz, then by using Step3 from above gets to the same values of the uninstalled ram and when I put them all they have the same value of 800mhz, and my pc boots up.

Questions:

1. Do you think this is the case?
2. What do you think is the issue, 1 ram slot from the motherboard or the ram itself? But my guess is that it can't be the ram itself as it wouldnt boot at all.
3. Do you know a permanent fix?

Thanks

 

[Karadjgne]

Default setting for DDR4 is 2133MHz. If the ram locks down, it's set properly, can't be loose. Personally, I've never seen DDR4 clocked at 800MHz, not seen ram clock that low since DDR2, DDR4 doesn't even have Jedec tables to go that low. Probably that 800MHz is Data Rate you are reading, putting the ram at 1600MHz DDR but even that's incredibly low, so I'm not sure what's up with that. The only explanation I can figure is that the cpu isn't seated squarely or there's a bent pin in the socket and your bump is scrambling the memory controller.

 

[Ciprian.ss]

Motherboard is Asus Z170-K

It happened again today, there are 4 Ram Slots with 2 Pairs I suppose, that's why there are 2 Black slots and 2 Grey Slots.
So, i've did the same as previously until all 4 booted again, then I've overclocked to 2666mhz all 4 and it didn't boot at all now, so I removed only one frome the middle grey slot and left only 3x 4gb Rams installed overclocked at 2666mhz and it booted up. Now I'm assuming there is a connection issue between the 2grey slots on the motherboard? Or the middle grey one has issuses in the pins or whatever they are called?

 

[Karadjgne]

Or could be a mis-aligned pin inside the socket, cpu cooler not tightened down correctly and putting pressure on the right side where the memory controller is. Or could be an unstable bios where bumping the ram voltage 0.05v could solve everything. Or the VCCIO. Or the VCCSA.

You bump the pc, and the ram goes funky. You could bang on the side of the pc and it'd still be seriously doubtful you'd get any movement in the ram whatsoever. Having a giant chunk of aluminium that's loosely held in by a couple of screws and hanging well away from the motherboards center of gravity, shake or vibrate or even bounce is a far more plausible situation.