Re: 6gb of ram but task manager says 4?
I had a situation like this before and I don't know if this applied to your motherboard. It may be that your motherboard does not see more than 4 gig of memory.
I had an AMD X2 system with 3 gig memory but the board only saw two gig. Windows will report seeing 3 gig memory but everything else says two.
I think this is such your case.
I yam what I yam