[nicozeg]

I had plans of making a testing system slowly going, but last week a local retailer offered me to test a couple new coolers just arrived. Had to hurry up things and test with what was available.

The goal is being able to test complete "cooling solutions". That means heatsink/fan combos or water systems as a whole.

-Tests are made in a somewhat old AMD system with a 1900+ Palomino.
-The main equipment for acquiring temps is a CHY 503 K/J thermometer.
-One K thermocouple is bonded undercore on the cpu, another is held a couple cm. away from the air intake.
-BurnK7 is used for at least 30 minutes before taking temp readings.

After some test it was clear that the undercore sensor was excellent, it reacted quickly to load, and when stability is reached readings are absolutely stable on the 0.1°C resolution display.

The difficulties start with ambient readings: Temps show great variations as air currents inside the room bring waves of hot air from the heatsink outlet.

The CHY thermometer has an average function, so this problem was minimized by reading the average of a 5 minutes lapse. This worked very well on radiator type coolers, where air flows in a straight path from one side to the other. In that case the intake air is almost the same as overall room temp.

The real problem happens on traditional heatsinks. As air flows to the mainboard and has to turn to the sides, a lot of it is recirculated by the fan. On average intake readings were about 4°C higher than room! Even worst is that some areas of the fan draw more recirculating air, while others fresh room air, so small variations on Tc positioning have big impact on readings.

That why I’m seeking advice from the more experienced ones here of what can be an acceptable way of acquiring ambient temps.

Here are some pics of my setup: