This is really annoying. It saw all 6 gigs last night. Now, just got home from work... 3.99gb usable again. I've made no changes.
Resource Monitor shows 2057mb reserved.
It's a bad memory slot. I tried each stick invidually, and the system won't even POST with a stick in slot 1 by itself. Every other slot posts fine. If I install 4 gigs in 3 and 5, it shows 4 gigs usable. 1 and 3, 2 gigs usable.
Your symptoms are synonymous with mine when I had thought I had a bad memory slot, but ended up having too much pressure on the socket. I know I've mentioned it a million times before, but I can't help but think about it when I see someone experience the same issues as me running a Venomous-X