Just bought a E7400 to run my NAS rig, and plan on some OC. I've paired it with a spare mobo (Asus P5N7A-VM), and currently it's cooled by a stock Q9550 HSF as it has a copper base and is slightly taller than the stock E7400 HSF. I'm trying to keep costs low so I'm hoping not to have to get an aftermarket cooler (I have 4 Zalmans, a NT06, a TRUE and a V10 on my other rigs). I do have a 140mm Xigmatek fan mounted above the CPU and aimed directly at it (CM Gladiator casing), so hopefully that will help a bit.

Will post my results here later.. but for now, I'll be reading up on earlier posts to see what people have achieved.

Just went to 3.5GHz (10.5x333) @stock Vcore using the Q9550 stock HSF in first attempt. At full load (folding) temps are around 55-58C. This is the SLB9Y (R0 stepping). Will let it run 24 hours and if stable then will try it with one of the many Intel stock HSF I have - probably the one that looks beefiest in size and fan power; and see if the older bigger HSF is better than the newer slim ones. Then later will push speeds higher.

Am getting <60C with my dinky stock HSF already In any case, if I can achieve a decent OC with the stock HSF, I'll be satisfied as I don't want to spend any more $$ on aftermarket coolers. If I really need to, I can swap in my NT06.

Folding uses 100% constant CPU loading. The Q9550 HSF is marginally taller, has a round copper base (E7400 is full aluminum) and 7.2W Delta fan (E7400 has a 2.4W Nidec fan).

3.5GHz is the same as my E7400 also at stock Vcore and been running stable at full load 24/7 for past couple of days.