People seem to be confused here...
The 3000+ multi is locked upwards at 9X. (that means you cannot go HIGHER than 9X on multi...but you can go lower.)
The 3500+ is locked upwards at 11X (again...you can't go past 11X...but you can go LOWER)
So, The 3000+ requires a HUGE RAM overclock compared to the 3500+ to get the same overclock.
9*290 = 2610
11*237 = 2607
That's a whopping 53MHz difference in RAM overclocking. So if you plan on hitting 2.6GHz with your 3000+ plan on buying some expensive overclocking RAM, or running a pretty big ratio (i dunno 5:4 or something.
With a 3500+ you can get a relatively cheap pair of CH-5's (say ~$120 kit) and hit 2.6GHz easily) OR if you have a $300 kit of RAM already that will do 310MHz then turn the multi down and run a better HTT to hit 2.6GHz...the point is if you dont have RAM capable of doing 290MHz+ then you will not hit 2.6GHz on a 3000+ running 1:1.
I choose the 3200+, its upwards locked at 10...a nice and even #. I only need average performing RAM to hit 2.6GHz (10*260) and i like that. Running ratios like 5:4 is not what i like, it cuts yourt bandwidth if you have to lower your HTT alot.