Welcome to Seven Forums Jeremy.
Check the msconfig setting mentioned by Thelen.
If that isn't it then we can try something else.
If you are overclocking tell us what the settings are at, both CPU and RAM.
Post the CPU and Memory tabs from CPUZ
Check your temperatures with Real Temp
, and post the temps at idle.
What amount of RAM is showing in BIOS?
Open Windows Task Manager, click 'Resource Monitor' in the 'Memory' tab, tell us what it says under 'Physical Memory'.
If the above info confirms the 9.99GB usable.
Burn the ISO to a CD using Iso Recorder
Boot from the CD, and run at least 5 passes.
If you get any errors, take out all but one stick, run at least 5 passes with Memtest86.
Your looking for bad RAM sticks and bad slots.
If you get an error, change to a known good stick and run the test in the same slot.
Test all sticks and all slots even if you find a bad one.
Be sure to unplug the power plug, and use a static/grounding wrist strap.