missing ram

[Pc.robb]

Hey guys, for some reason windows 7 is only seeing 7.23gb of ram, yesterday it was displaying the full 8gb, any ideas on how to get it back or why it's gone?

 

[Pc.robb]

Intel core i5 [email protected]
8gb Kingston hpyer x 1600mhz
Gtx 9800gt 1gb
windows 7 home premium 64 BIT
Asus P8Z68-v
Seagate barracude 1tb

The 7.23gb was shown on the windows experince page under "system"