- Joined
- Aug 20, 2002
- Location
- Brooklyn, NY
Gallery Pics
http://www.ocforums.com/showpost.php?p=1622809&postcount=51
I’ve received messages from people asking about the performance of my WhatBlock waterblock. I was reluctant to say anything until I could perform tests that were reasonably accurate. I finally acquired the equipment necessary, so here is a very preliminary report of WhatBlock performance.
Test Environment – Test Computer
1600+ Athlon XP Palomino at stock speed
Max power output 62.8 watts
Abit KT7A motherboard
BurnK7 running at high priority
Task Manager process count = 15
Task Manager closed during testing
AMD on-die thermal diode isolated and monitored with diode reader
Test Environment – Monitoring Computer
2200+ Athlon XP Tbred running stock
Asus A7N266-VM motherboard
Monitoring diode reader through SMBus and Motherboard Monitor
Test Environment – Water Rig
Mag 2 pump submerged in plastic tub
Water supply – Continuous stream from faucet into plastic tub
- heated water was drained...no recycling of water.
Water rate: 1.0 GPM
Water temp at suction: 30.5C (0.0C variance during testing period)
Thermometer: Electro-Therm SH66A 0.1C resolution 0.2C accuracy
Test Results:
CPU temp = 40C
CPUTemp - WaterInTemp = 9.5C
Accuracy = +/- 1.2C
NOTE: Upon calibration review, CPUTemp – WaterInTemp may become 12.0C
What this means is that if the water temperature in your cooling rig is 30.5C, and the water is flowing at 1GPM, then the temperature of your 1600+ Palomino will be 40C while running BurnK7.
This should have been the final performance review. However during testing a calibration anomaly was noticed that still has to be resolved.
I was trying to make my results directly comparable to pHaestus’s results on Procooling.com. His waterblock rating is simply a temperature difference at a given flowrate. I got an accurate thermometer, and I also made a diode reader for accurate CPU temperature readings. I figured I’d do a test at 1 GPM and leave it at that for now.
In this article pHaestus described his testing process:
http://www.procooling.com/articles/html/procooling_testing_methods_-_p.php
He also describes his waterbath calibration method here:
http://www.procooling.com/articles/html/amd_thermal_diode_testing_cali.php
The first problem I have is that my processor is hotter than the one pHaestus is actually using. I thought he was using a 1600+ Palomino but he’s really using a 1700+ Tbred, which is 13.4 watts cooler than my processor. I figured I could underclock my processor, but the Palomino core is larger than the Tbred core so that throws things off as well so...I’m still working on that.
The big problem, though, is calibration. I performed a water bath calibration as he did, and got the same results. The CPU temperature readings were linear and in sync with the thermometer from 20C to 50C. I thought this was great. Then, another idea came to me. I wanted to check the temperature of the CPU while it was mounted in the motherboard by running water, at a specific temperature, through the waterblock and then checking the diode temp. I figured if the waterblock can remove heat, it could also deliver heat. So I set up the test to see if I’d get the same results as the water bath. The testing condition was exactly the same as for testing the waterblock, only the psu on the test computer was switched off so there was no power to the board. This is what I got:
Water: 19.5C, CPU: 18C
Water: 30C, CPU: 28C
Water: 50C, CPU: 47C
Not only was the CPU cooler, but the differences weren’t linear! I thought maybe EMF from the pump, but the temperature readings remained the same when the pump was suddenly switched off. I don't think EMF from the Monitoring Computer was causing the problem because it was on during the water bath test. Currently I am at a loss to understand why the “waterblock calibration” method didn’t work. I’m pretty darn sure it’s not electrical.
I do not know if pHaestus ever performed such a test. For all I know, his results could be reading low as well. Or my results might be just fine under a powered PC. I do not think pHaestus, or anyone else, has figured out how to calibrate the CPU diode while under actual test conditions (waterblock installed and with CPU powered.)
Anyways, since the difference between the thermometer and diode would seem to be around 2.5C at 40C, I listed a possible corrected temperature difference of 12.0C.
I’m open to all suggestions and comments.
EDIT: Changed GPH to GPM
Last edited: