Maybe the reason for you Ram issues is because most of the updated Bios revisions are having Ram compatibility issues, people that own Asus motherboards really need to have a look at Asus's own forums so you know when not to update your Bios. I am still on the bios that came with my mobo and have had no problems, just because you can update your Bios doesn't mean that you should.
A lot of people out there often update their Bios simply because they can, this only causes them more trouble in the end and needless suffering. I wish Asus would test their Bios revisions before that release them instead of unknowingly put you the customers as the beta testers. Thats just a heads up for all you, ever wonder why the Bios that comes with your mobo usually is best out of the box? Because if mobo makers release mobo with bad Bios versions out of the box they would lose customers left & right.
On my older Asus P5B Deluxe from last year from which I never once updated my Bios and had that mobo for quite sometime without so much as a problem with the Bios that came with the mobo. Its still a very strong gaming computer, think about if you are having any problems with your current Bios and if not then I see no reason why you would update it. So unless you are having issues with the mobo out of the box, that is the time to update your Bios, but not before you check the Asus forums for info on how the new Bios behaves with others computers to avoid that bad Bios.
Asus'a own forum, beaware that sometimes its very busy so try again later>>
http://vip.asus.com/forum/topic.aspx?board_id=1&model=P5E&SLanguage=en-us