UD5 detects less RAM only on reboot(cold boot OK)

[Alphatrack]

Hello everyone,

I am sorry to make my first post here with a question, but I am starting to lose all hope.

I have a EX58 UD5 motherboard (Rev.1.0), with the F10 Bios. I have 12GB of Corsair RAM(2x Corsair 6GB DDR3-1600 Ram Kit (3 x 2GB, PC3 12800, 9-9-9-24, TR3X6G1600C9).

The problem I am having is that the BIOS detects less RAM (most of the times 10GB) when I reboot my PC. The weird thing is that this happens ONLY when I reboot. If I start a cold boot, then all 12GB's are detected. I have tried all the suggestions for similar problems like, setting manually the timings, changing voltage, change RAM speed (BIOS sets it at 1033 by default). I tested each module and they work fine.

When the system does detect 12GB after a cold reboot, Windows 7 64bit work flawlessly and I can use all 12GBs of RAM without any problem whatsoever.

Right now my only option is to never reboot my system and perform only shutdowns and cold reboots.

I have sent a support ticket to Gigabyte and I am expecting a reply.

Could it be a problem with the BIOS? This could be the only logical explanation, otherwise, why on earth does it see 12GB on cold
boot but only 10 on restart?

Thank you in advance for any replies!

[Dark Mantis]

Whilst it seems to be logical that it is a BIOS problem, and chances are it is, the other thing that causes this problem is bent pins on the CPU socket. Now I know that sounds stupid but believe me it has happened quite a few times recently here on the forum so it is worth checking.

[Alphatrack]

Hello,

I have checked it, the pins all seem good.

[Dark Mantis]

That's good news anyway. So that really leaves us with the BIOS. When you checked the modules did you do it one at a time and use Memtest86+?

[Alphatrack]

That's good news anyway. So that really leaves us with the BIOS. When you checked the modules did you do it one at a time and use Memtest86+?

Yes, no errors with each module. I was mistaked in my first post, my BIOS version is F12, not F10.

[Dark Mantis]

The only other update available on the website is F13j which is a beta version but it should be stable and trouble free or it wouldn't have got as far as the site. I don't know if you want to try this one and see if it helps?

[Alphatrack]

I am a bit hesitant to try a Beta BIOS, but I would be happy to try it if there was a sign that this would fix the problem. As far as I can see this BIOS update only affects keyboard compatibility and the internal soundcard.

No mention about Memory issues whatsoever 

I am not sure if I should in fact downgrade my BIOS to a version that was admittedly stable though.

[Dark Mantis]

The trouble with the BIOS updates is that the information on what they cover is always rather sketchy. It can be a bit of a gamble on whether it will help you or not.

[Alphatrack]

OK, just an update.

Today I switched off my PC, then booted it again and nothing came on the screen, it wouldn't get in the BIOS and it just did one long beep and two short beeps.

I had to let it for 2-3 minutes in order to let me get in the BIOS. After that it booted normally.

Either there is something terribly wrong with the BIOS or my motherboard is dying.

Please, if you have any suggestions I would be glad to hear before I return the motherboard.

Thank you

[Dark Mantis]

One long and two short beeps means the graphics card or monitor is a problem. It might be worth reseating the graphics card and checking the power conmnections on it.

[Alphatrack]

Jut wanted to update you guys:

I went my motherboard for replacement. They replaced it with a new UD5 and guess what: Problem still there even with the brand new motherboard.

Next in line is checking the CPU. 

[Dark Mantis]

As a matter of interest what PSU are you using?

[Alphatrack]

Hey Dark Mantis,

I am using a Corsair 750 Watt PSU which has very good efficiency.

I am really starting to believe that there is something wrong with the UD5 motherboards as a model, like they cannot work out big amounts of RAM. It is really strange that a second motherboard exhibits the same exact problem. On Monday the service department will have another new UD5 delivered as well as a new CPU, if the problem persists there is no doubt that there is indeed something wrong and I am afraid I will have to change the motherboard model.

I spent two weeks trying to figure out what is wrong with my MOBO trying all kinds of BIOS settings I could find in this forum and other sources and now it seems that there is something else going wrong.

[Dark Mantis]

I am using a Corsair 750 Watt PSU which has very good efficiency.

I am really starting to believe that there is something wrong with the UD5 motherboards as a model, like they cannot work out big amounts of RAM. It is really strange that a second motherboard exhibits the same exact problem. On Monday the service department will have another new UD5 delivered as well as a new CPU, if the problem persists there is no doubt that there is indeed something wrong and I am afraid I will have to change the motherboard model.  

Well I think we can discount the PSU as the problem area. I don't really think that the UD5 has a problem with large amounts of RAM though as there are others running large amounts and I haven't heard anyone complaining of this problem. The UD5 is basically the same as the UD7 and UD9 and they definitely work ok. Please keep us informed of your progress with the new board and CPU.

[Alphatrack]

I certainly will, unfortunately I won't be having my PC until Monday, but I hope that the problem will be shorted with the new UD5 board. I will report back!