To test the ZOOMFLOW 240, we will be running 2 separate tests: one meant to torture the CPU and the other to provide more real-world temperature expectations. The first test will be done with a well-known program called Prime95 which will put extreme stress on the CPU and in turn generate massive amounts of heat. The second test will be using Cinebench R15 to simulate a more realistic workload that the majority of users will see.
To start our testing, we will let the system idle for 5 minutes to record the lowest idle temperature and then run Prime95 on “blend” mode for 20 minutes. At the end of the 20 minutes we record the Maximum and Average “Core Package” temperatures. After Prime95 testing is complete we let the computer idle until it hit its previous idle temperature. To generate a more realistic workload we run Cinebench 5 consecutive times and record both the Max and Average temperature of the core package.
The first set of tests were done on a stock i7 8700K which clocked each core at 4.3 GHz at the default voltage. This resulted in an idle temperature of 29c a while running Prime95 max temperature of 74c with an average temperature of 61c. Moving over to Cinebench after the 5 runs were ended with a max temperature of 63c with the average being 55c. These temperatures are quite good for a 240mm radiator and we should be able to push this 8700K quite a bit further.
Prime95 @ Stock (4.3GHz)
Cinebench @ Stock (4.3GHz)
For the next test we bumped our 8700K to 4.6GHz on all cores which was stable with a voltage of 1.3v. The idle temperature saw a 2c increase and after running our 20 minutes of Prime95 we had a new max temperature of 80c and an average of 63c. Doing our Cinebench runs we ended up with max temperature of 70c with an average of 62c. These temperatures are still well within the 8700K thermal limits so let’s see how far we can overclock this 8700K.
Prime95 @ 4.6GHz with 1.3v
Cinebench @ 4.6GHz with 1.3v
Moving into our last set of tests we managed to overclock the 8700K to 4.8GHz on all cores with a voltage of 1.355. We did attempt for a 4.9/5.0GHz clock as we think the ZOOMFLOW 240 can handle it but we couldn’t get it stable even with 1.45v. We again saw a slight increase in the idle temperature which is now 32c and after running our torture test we ended with a maximum temperature of 88c and an average of 67c. Our Cinebench results ended up with a maximum temperature of 77c and an average of 71c.
Prime95 @ 4.8GHz with 1.355v
Cinebench @ 4.8GHz with 1.355v
Overall the ZOOMFLOW 240 did an amazing job at keeping our 8700K cool and even with the tortuous Prime95 we didn’t even break 90c well running at 4.8GHz. This is quite impressive with having only a 240mm radiator and makes us wonder what kind of temps you could get with a delidded 8700K that could reach 5.0GHz+.
Below are some graphs of the above results: