I'm thinking of a processor & MB upgrade.
From what I'm seen the above two seem to fit my needs and budget. I'll likely couple either with an appropriate Asus board.
Any thoughts on either processor? or another direction altoghter?
my advice is unless you do a LOT of video editing or something where compling time matters then there is no need for the FX.
Xeons are server CPUs as someone else stated, not really good for home.
I would honestly suggest 2 things.
1. Phenom2 over the FX as it performs better and is cheaper and works in the AM3+ mobo WITHOUT a bios flash for sure.
Some of the AM3+ boards don't have the proper bios and you have to flash it, IMO not worth the trouble for something that isnt that much of an upgrade from a P2.
2. if your trying to save a bit of cash, get an AM3+ Mobo but put a Phenom 2 CPU in it. And avoid the ASUS ROG AM3+, herd so many problems with'em.
The AM3+ mobo will let you upgrade down the line if you need to, Intel's track record isn't good when it comes to socket life.
TL;DR Version. Get a phenom 2 CPU with a AM3+ mobo, but avoid the ROG line from ASUS on the AM3+ platform.