[SOLVED] HELP!!! 2 out of 4 DIMM slots not working

[RichardTan787]

I have recently built a PC and I have found that two of the four DIMM slots are not working. My CPU is an Core i7-8700k and I have a ASUS Prime z390-A motherboard. I have built computers in the past and all have worked 100% fine. The first error i received was the MemOK! LED turning on. My system fans seemed to be turning and CPU working, but the computer would not post. I suspected a bent CPU socket pin as I have tried single RAM sticks and tried them in different slots, updating the BIOS, and even reinstalling the entire system altogether. I have now found out that 2 of the 4 DIMM slots furthest from the CPU socket are not working, and if I try to put a stick of RAM in them, the system just doesn't post. If I put the two sticks of RAM in the 2 working slots, the system runs just fine. Can you guys shed some light on what's going on?

And if it is a bent CPU socket pin are there ways that I could fix it without just asking ASUS to repair it?

 

[Gfost73]

I am not saying this is the issue, but I have had a similar issue before, I build the system and for some reason only half the RAM was showing in the BIOS, which made me think the DIMM slots were bad, as I tested RAM and knew it was good, so believing the DIMM slots were bad and id have to replace board I removed CPU cooler and checked CPU pins etc and all were fine, so I put CPU back in socket, and just for a chuckle I thought Id check the system once again , and this time (believing it wouldn't be different) I just placed CPU cooler on chip and booted to Bios, well to my surprise all the RAM was showing , so I then reinstalled the CPU cooler, to discover that once again half the RAM was missing , I discovered then that one of the cooler standoff nuts wasn't quite right causing the cooler to press too much on one side of CPU I guess which caused issue, once I fixed that and made sure cooler was installed properly everything's worked fine since.. so maybe CPU cooler is not quite right pressings too much on one side .. but again I cannot say for sure, its just something Ive experienced that seems similar

 

[Gfost73]

and to straighten pins on the intel boards I'm not sure how easy it is, with AMD chips its quite easy, ive done it several times using a razor blade and wearing magnifying glasses. perhaps the intel boards would be as easy , but with the AMD chips you can line the pin row up with your eyes and look straight down to see if any are not right , so ill assume you wont have this advantage with pins on the board itself. im sure there would be youtube videos however to show how you should attempt it

 

[RichardTan787]

and to straighten pins on the intel boards I'm not sure how easy it is, with AMD chips its quite easy, ive done it several times using a razor blade and wearing magnifying glasses. perhaps the intel boards would be as easy , but with the AMD chips you can line the pin row up with your eyes and look straight down to see if any are not right , so ill assume you wont have this advantage with pins on the board itself. im sure there would be youtube videos however to show how you should attempt it

do you know if there is some way to use software to check if all CPU pins are ok, such as in the BIOS or a third part application?

 

[Gfost73]

no sorry I dont, ive always had AMD and unless the pins missing there normaly good to go, even if bent really bad, they are easy enough to streighten, if your careful, and my RAM issue I really discovered it myself was by accident. maybe try what I did and just set the CPU cooler on the chip (not tight) and boot to bios, if by luck (like happened to me) it all works then youd know, and if its still the same , well maybe those 2 slots are dead but couldn't say 100% that is the case either, but I would think so myself

 

[Gfost73]

do you know if there is some way to use software to check if all CPU pins are ok, such as in the BIOS or a third part application?

were you able to Resolve your issue? was it the CPU cooler being installed improperly? just curious =)