Windows 7 reporting 15.5GB usable

[CharlieWalkerTX]

OK....I built a new system about 5 months ago and I kept updated on new BIOS's that have been released for the motherboard. Ever since now Windows 7 Professional 64 bit is reporting only 15.5 GB usable out of 16 GB. I have disabled the IGPU and memory remapping

My system specs are

Motherboard: ASUS Maximus IV Extreme-Z
RAM: CORSAIR Vengeance 16GB low profile
Video card: two EVGA GTX 580 SLI
CPU: i7 2600K@4.6GHz

 

[geekapproved]

You'll probably never even use more than 6GB, 4GB if gaming, so why are you worried about .5 GB?

 

[oobymach]

I know this is an older post but I just had the same issue, after swapping sticks, manually adjusting timings, voltage, I found that cool n quiet had somehow been re-enabled so I disabled it and booted to windows and found all 16gb usable again.