Hey.. that's exactly the same Case that I'm using. I managed to improve the airflow significantly by having placing a high RPM fan at the front (like what u did with the CM), but I'm using a Vizo Freezer fan. Better if you had the Silverstone FM121 'cos I feel the air vents in Front is kinda blocked by the Ports. At the rear, I switched to the Silverstone FM123 w/ controller which helped quite a bit. But IMHO, you should invest in an aftermarket CPU cooler cos the stock ones have trouble dissipating the heat (as what I experienced). The mods that I made have dropped by idle load temperature from avg. 59 C to about 50 C at normal room temperature (no air-con). At night, it goes down to a sweet 41 C (aircon) at idle load.

P/s: Waiting for Ian to insert a side panel fan for my casing to improve airflow

Actually your cpu temp is quite good eventhough when u say during afternoon with a high ambient temp you're looking at 40 C (idle). What I can suggest is to improve airflow. I'm modding my side panel to place a Silverstone FM82 fan to suck in air into my proc, whilst my rear Silverstone FM123 will blow out the hot air which dissipates from my proc. Will let you know how it goes when I finish getting my panel back.

P/s: what thermal paste r u using? that might help a lil

Oic. somehow in my opinion those 'stock' thermalpaste (i.e. no name) are quite inferior. like the one i received with my Xigmatek cooler, dunno cap ayam one, in a small plastic bag. that's why i used either ArticSilver or Tuniq.

I'll post a pic of my rig after I set it up. Going to LYP to buy my new Phenom X4 proc after work.

The Vizo fan. Is it the "FREEZER" type? I think that's quite lousy. Hardly any airflow. Regret buying it. Might sell it off and buy a new one though.

I test OC'ed my new Phenom X4 2.2Ghz (to 2.4Ghz) and it seems to be running well. Full load < 60 C.

Will try to OC it to 2.6Ghz later tonight and stress test it