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Testing and benchmarking
Now that the system is hooked up to the cooling solution let's run some tests. Initial thoughts... decent cooling.
The CPU core is running steady at a 42 C temperature at idle. As part of the test we maxed the workload of the CPU to 100%, managing some serious encoding work.
The fun part is, the temperature does not rise that much with a full 100% workload, it only differed a couple of degrees but basically that's it. This creates some nice overclocking potential. I must admit that the previous copper air (fan) cooling block already was a high output fan, quite expensive and very effective.
Cooling method versus temperature in degrees C. The lower the better.
| Watercooling | IDLE | 100% |
| AIR CPU @ 2.8 GHz | 42 | 58 |
| AIR CPU @ 3.4 GHz | 48 | 67 |
| H2O CPU @ 2.8 GHz LOW | 42 | 51 |
| H2O CPU @ 2.8 GHz HIGH | 43 | 52 |
| H2O CPU @ 3.4 GHz LOW | 44 | 54 |
| H2O CPU @ 3.4 GHz HIGH | 43 | 53 |
AIR CPU = Traditional fan cooling (a high performnce SilenX copper base fan btw)
H2O CPU = the watercooling kit used.
2.8 GHz is the clock frequency of the processor, 3.4 GHz is that same processor yet overclocked 600 MHz.
These are the results with the control unit set at low (uses 7 volts) and high (uses 12 volts). At the highest setting the drive bay radiator fan made moderately more noise, actually to a level that is quite annoying for me personally.
CPU Cooling - As you can see compared to traditional air-cooling at idle we have a 1 degree difference. At 100% processor utilization that difference is better with watercooling maximum of 51-52 degrees C.
When we relate this to overclocking, your results are going to be limited by the model of CPU that you have. Our Pentium 4 is a nice overclocker, we knew that in advance and despite the excellent cooling we could not OC it much further then 3.4 GHz, which we saw with traditional air cooling. Looking closely at the graph you'll notice that watercooling is very constant. Air-cooling peaks out a 100% utilization a tad more. Still at idle I would have liked to see somewhat better temperatures though.
As you can see the kit solution offers nice tweaking possibilities for your system without an extremely noisy environment, it is able to absorb heat quite sufficiently. On the other hand, a good active fan can get these results also.
