H100i how can I check the coolant temperature?

[Jimbo2027]

A couple of days ago the link software stopped working (I reinstalled it but it still failed). So I connected the fans directly to my main boards CPU and optional CPU headers and removed the USB cable connecting the control unit to the main board.

 

I ran IntelBurnTest and the CPU can go upto 56c when looking at HWMonitor. How can I check the coolant temperature and that the pump isn't going to overheat without the link software? The radiator isn't very warm and the air coming out of the fans isn't hot.

[c-attack]

You can't, although most people operate just fine without ever knowing the coolant temperature. When under load, your coolant temperature will always be substantially less than load CPU temperatures. You will hit CPU thermal shutdown before you get in trouble with the actual temperature of the water inside the cooler. I can't be very precise without any hardware information, but an Intel CPU that only hits 56C CPU temp on IBT probably only has a coolant temperature in the 25-35C range. That value is helpful when diagnosing problems or when learning how the cooler works, but it is not essential to successful operation. You may find your fans change speed quite a bit more often when running from motherboard control, but that certainly doesn't adversely affect the system -- only sensitive ears.

[Jimbo2027]

Thanks, I feel less worried it will fail on me now. My CPU is an i7 6700k @ stock speed. The temps playing games go up to 45 ever and the CPU idles at 30.

[c-attack]

Yes, those are pretty much as expected. Idle temperature will change seasonally (or not if you're tropical). Most people run 4-7C over the room temperature. Make the room cold and the idle and all other temps will drop. Reverse in the Summer months.

 

You will get some warning if the pump is weakening. This is generally seen in a higher than expected idle which in turn leads to higher than expected average load temps. Don't give too much weight too peak values. There are many reasons a temp spike may occur. Almost none of them have to do with the cooler. If the issue is becoming more severe, you will see the idle temp continue to rise after boot. Rather than level off after 5-10 minutes, it will continue to climb. At that point, most use is affected and you will notice the temperature changes. No reason to fret about this daily. Even if the pump goes, the big advantage of a water system is its capacity to hold heat. You will not fry your CPU or even hit thermal shutdown like you might on an air tower or smaller fan cooler. This gives you some time to recognize the problem and take appropriate action.