Gigabyte z87x UD3H first two RAM slot's not working

[Antizipated]

Hello again, finally got my PC up and running!

Long story short I noticed that I only have 4gb of RAM showing in the UEFI BIOS. I've tried both stick's of RAM and they both work fine, apart from 4 and 2 (the ones physically closest to the CPU) I'm guessing that I might not have "enabled them", however I thought this would be automatic. Any help would be appreciated, specs below.

Gigabyte z87x UD3H
Corsair Vengeance 2x4gb ver8,16 1.5 volt RAM sticks.

 

[Antizipated]

Just to elaborate, the RAM sticks are working fine, the slot's 4 and 2 aren't. I doubt they're faulty.

 

[Antizipated]

Just to elaborate, the RAM sticks are working fine, the slot's 4 and 2 aren't. I doubt they're faulty.

 

[babernet_1]

Just to elaborate, the RAM sticks are working fine, the slot's 4 and 2 aren't. I doubt they're faulty.

I just downloaded the manual and checked. For using just two RAM sticks they need to be in either slots (1 and 2) or (3 and 4.)

The slots are numbered 4 2 3 1 with 4 nearest the CPU.

 

[Antizipated]

Just to elaborate, the RAM sticks are working fine, the slot's 4 and 2 aren't. I doubt they're faulty.

I just downloaded the manual and checked. For using just two RAM sticks they need to be in either slots (1 and 2) or (3 and 4.)

The slots are numbered 4 2 3 1 with 4 nearest the CPU.

I've tried both configurations and the slot's on their own, it won't boot whe using either of those in in a single or dual config.

 

[babernet_1]

Sometimes for problems like this you need to reset the CMOS. There may be bad information in the system causing problems with reading ram in those slots. Make sure your drivers are updated too.

 

[Antizipated]

Update - CMOS reset got me back into the BIOS with one stick of ram, but with two the whole computer starts up, shows debug LED 15 and then shuts down (nothing on monitor).

 

[alexoiu]

RAM slots not working are usually related to CPU socket bent pins. I suggest reseating the CPU and checking the socket for bent pins.

 

[Antizipated]

I'll reseat the CPU tomorrow, it's a brand new one (RMA'd old one) so it SHOULD be fine, and I've got a day off to troubleshoot. Always worth a try though. Is there any other reason (apart from the mobo being faulty) that the slot's wouldn't be working?

 

[alexoiu]

Apart from the board's CPU socket, a short might cause similar issues (if an extra standoff would short the board, for example).

 

[Antizipated]

Reseated the CPU (no bent pins) and breadboarded again, looks like it's the motherboard. Quick question, will I have to get a new copy of windows if I send this motherboard back as I've installed an OEM copy of Windows 7 and are there any drawbacks to using 1 stick of 8gb RAM instead?

Thanks for all the help, at least I've learnt a lot more about building a computer!

 

[babernet_1]

Not sure about the windows install, but using just one RAM stick will have a definite negative impact on performance.

 

[Antizipated]

How bad would it be? EDIT: looked it up, it's not worth the hit in performance. I'll return it for another and buy a new copy of windows, shame.

 

[Antizipated]

RMA'd the board and the new one is working perfectly. I think there was a scratch on the PCB which most likely caused the problem, thanks for all the help!

 

[babernet_1]

RMA'd the board and the new one is working perfectly. I think there was a scratch on the PCB which most likely caused the problem, thanks for all the help!

Thanks for the update. Be sure to vote for the best message.