Overclocking my Q6600

[Cptobvious]

I just built myself a new rig and I'm looking to overclock the cpu now to around 3.0ghz. Its a G0 revision. I was fooling around in BIOS with the AI Overclocking on the Asus Maximus Formula (Not the windows app, but in BIOS) It lets you set it to a Q6850 and adjusts all the parameters for you. I ran it for a few hours last night and it seemed to be ok, then I set it back to stock. Anyone else had any success with this? Also was wondering what frequency to keep the RAM at when its clocked at 3.0ghz.

Today im looking to go buy a cooling solution so I can keep it overclocked. On the stock cooling idle, the cores were reaching around 47-49 degrees. It said the CPU was at like 32-34 the whole time though. Not sure which is the temp that really matters.
I was considering getting this fan: http://www.canadacomputers.com/main.php?do=ShowProduct&cmd=pd&pid=008162&cid=FN.349
or the AC7Pro: http://www.canadacomputers.com/main.php?do=ShowProduct&cmd=pd&pid=013470&cid=FN.349
or the Scythe: http://www.canadacomputers.com/main.php?do=ShowProduct&cmd=pd&pid=013081&cid=FN.349
Is this a good fan for keeping the Q6600 at safe temps @ 3.0-3.2ghz?

I have a Antec 900 case also, so fitting may be an issue for some of these.