SUMMARY: Paying attention to secondary heat sources can drop CPU temps by a few extra degrees.
As I do more heatsink testing, I am monitoring not only CPU temps but the CPU’s back and side temp core temps as well. One heat source on all motherboards are the power transistors, and I put a fan over the six of them that the ABIT KT7 features. They don’t run particularly hot (around 35C/95F) but I placed a 60 x 15 mm fan over them to see what would happen.
As the pic above shows, I just laid the fan over the capacitors around the power transistors and let it run. To my surprise, rear CPU temps start to fall (running Prime95, Duron 800 @ 1000, 1.93 volts)! As the table below shows, temps across the board were lower:
| Condition | CPU Back Temp | CPU Side Temp | MBM 417 Temp |
| No Extra Fan | 55.2C/131.4F | 45.6C/114/1F | 42C/108F |
| Extra Top Fan | 53.9C/129.0F | 45.0C/113.0F | 41C/106F |
I placed a probe on the back of the board, underneath the socket, and recorded a temp of 37.2C/99.0F.
Hey – this is getting interesting! So I then decide to lift the motherboard up and get some air to the back of the board in addition to the top, as shown below:
With this added cooling, I drop back CPU temps by 2.6C/4.7F – about a 5% temperature decrease. The temp probe on the back of the motherboard now shows 29.0C/84.2F – Not bad!
| Condition | CPU Back Temp | CPU Side Temp | MBM 417 Temp |
| No Extra Fan | 55.2C/131.4F | 45.6C/114/1F | 42C/108F |
| Extra Top Fan | 53.9C/129.0F | 45.0C/113.0F | 41C/106F |
| Top + Bottom Fans | 52.6C/126.7F | 44.6C/112.3F | 38C/100F |
The point of all this is that you might be surprised what a little extra air flow in the right places can do for you. Feel around your motherboard (carefully) and if you detect some hotspots, a fan directed at it might yield some unexpected dividends. These are “free” temp reductions just waiting to be found.
Be the first to comment