dchampion1991

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Mar 13, 2012
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Before we hop on the there is a search button for a reason bandwagon I have indeed used it but nothing seems to be working for me.

I have 12 GBs of ram that all work with my motherboard. For about 3 months all the ram worked fine, I restarted my computer and now only 8gb is usable?? I took a screen shot so you can see that it shows i have all 12 GB but only 8 is usable. I have updated the BIOS I have done the msconfig thing and i cant get this to work.

Any help would be appreciated greatly.

screen01oemblackedout.jpg
 

cTs Corvette

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Aug 17, 2011
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I'd suggest a Google search-it seems there are lots of possible solutions, some of which you have already tried, and some of which seem really strange, like re-seating your CPU fan, but several people swear it worked for them. Another possibility is incorrect RAM timings in BIOS, and RAM reserved for hardware, which you can check from the Resource Monitor.
 
If you've been in your bios recently you may have mucked around with the PCI address mapping. This is used to make addressable memory on peripheral devices accessible to the OS. On legacy systems (IE, OSes not running in long mode, AKA 64 bit mode) this was still confined to the 32 bit address space and was taken out of the 4GB of addressable memory which resulted in the infamous 3.25GB of usable memory on a 4GB system problem. This same problem occurs on 64 bit systems when the bios is not properly configured to map the addresses to a higher range and the result is that 8GB can look like 7.2, 12 can look like 8, etc... it all depends on the particular system. Take a look around for this
 

rpgplayer

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What is the RAM capacity listed in bios?

[edit] More importantly, what is your ram configuration? I ask because the board you list has 4 slots, but the only way to get 12gb on 4 slots is by using 3 4gb sticks. That could be your problem.
 

cTs Corvette

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2 x 4GB + 2 x 2GB = 12GB

That would be my guess for his configuration.
 

cTs Corvette

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Well, looking at those specs, one of them calls for 1.65V and one calls for 1.5V, and it's the 2 x 2GB sticks that call for 1.65V. You shouldn't have an issue if you bump up the voltage enough to make the 2 x 2GB sticks happy-check in BIOS and see what voltage it's running at now, and if it is lower than 1.65V, bump it up and see if that solves it.

Probably your BIOS update killed your overclock, if you had one before. Or maybe the old version of the BIOS was better able to deal with 2 different voltage requirements.
 

Yep, ^ that is where I was heading too.

Mobos can handle all kind of RAM's, but different voltage between other sticks can do just this!
 

dchampion1991

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Mar 13, 2012
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i got it to show the ram and it said only 8191MB so it is only seeing 8GB. How can i update the BIOS to fix this since the MOBO supports different voltages and up to 16GB? I do not have the original MOBO disk