I have a Core i7 920 & Gigabyte UD5-X58 Motherboard and I've just purchased 24GB of Mushkin memory to upgrade from my 6GB of Corsair Memory. My operating system is Windows Server 2008 R2 (Which is a 64-bit Operating System)
I am having an issue where only 5.5GB is being detected by the system. I have two Highpoint 2320 RAID Cards and I think they are each reserving 256MB of that memory (taking it from 6GB to 5.5GB even when I had 6GB of Memory installed) but with 24GB installed I am still only able to use 5.5GB instead of 23.5GB which is what I expected.
The BIOS detects all 24GB, as does Windows itself, specifically Windows says 24GB (5.5GB usable) and in Task Manager it also reads only 5629MB next to 'Total' for the memory amount.
So far I have tried the following steps and none of these have changed the system from reporting 5.5GB:
Removing 1 Dimm from Slot 6
Swapping 2 Dimms around
Increasing VTT voltage to 1.35v
Increasing Memory voltage from 1.5v (recommended) to 1.6v
Clearing CMOS and running 'vanilla'
The most confusing part of this is that to me it should be reporting at-least 8GB or 7.5GB since all my ram is 4GB modules, instead it is reporting 5.5GB which is one full module (4GB) and half of another module (2GB) - How is this even possible?
I've done a lot of Googling and this does seem to be a common issue on x58 boards but I have previously been able to get this board to detect 10GB of memory when I used it for my desktop system instead of as a server system so I know it is technically able to detect more memory but it appears Windows Server 2008 R2 does not want to address it.
I really need some help here, and before anyone asks why I need 24GB of memory this is being used for a Server with a lot of VM's not for playing Crysis
![Grin ;D](http://forum.giga-byte.co.uk/Smileys/default/grin.gif)