I am running fine as well. e8400 4 gigs of ram 4870 1 gig graphics card.
What I remember though is that because we had problems with optimization with DCS a-10c is that I disabled alot of things in my bios. CIE, multithreading and the like. Don't know if this is responsible but be aware that although you have decent hardware that many MANY software things can wreak havoc.
also if you have 2 graphics cards for multiple screens etc, try just using your best graphics card. many users on Eagle Dynamics forums had good results with this.
edit link:
http://forums.eagle.ru/showthread.php?t=68060