Here's a link about the 650i you might want to check up on.
http://forums.anandtech.com/messageview.aspx?catid=29&threadid=1972653&frmKeyword=&STARTPAGE=92&FTVAR_FORUMVIEWTMP=Linear
There is a bit overkill listed on cooling - the southbridge doesn't run nearly as hot as I thought it would so you can use any dinky heatsink on it to cover it while you overclock (even then, some people have gone without it with no problems but not recommended.) Salvage old computers or just buy a cheapo one. Also, you should probably buy a small fan to screw into the stock heatsink of the northbridge - that one does run hot. Really hot. You can overclock without adding additional cooling but honestly, every bit counts for this one. I used the combination COOLER MASTER SLC-S41-U1 for cooling. Basically, I unscrewed the top fan and used that on the NB and the heatsink on the SB. The NB still may need additional cooling or good airflow beyond that depending on other factors. Be careful when applying the fan or take off the heatsink entirely to reapply AS5 or whatever after you clean up. Probably cheaper to buy a small heatsink with a small fan instead of that particular one. Just remember, if you want to use sli, you'll have to get something that isn't in the way of your second card.
I could have easily opened some of my old comps and swiped off fans from the those though. I eventually did which made some of my additional cooling purchases invalid. Took apart an old Antec smartpower PSU that was dying and redid some wire/connectors for example for some really high powered but relatively quiet fans.
If you shop at newegg, do not buy the arctic freezer pro 7. It's not worth 60 dollars as that's tuniq tower price range.
The latest bios (401) is great. Lots of people love it, me included. I did have to reset the CMOS after because I couldn't get into the bios even though my computer booted fine. Just reset the CMOS to save yourself the headache after updating.