CPU_FAN error on start up, Temps rising in bios, same result with two different coolers

Davethesculptor

Prominent
May 13, 2017
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510
SUMMARY
Corsair Hydro H115i - CPU_Fan error and rising temps in BIOS > I make sure everything is plugged in and try alternate ports.

I uninstall it and take it to the store for warranty.

a week later I install my old cooling system a Corsair Hydro H110i and get the same CPU_FAN error and rising temperatures in bios but it stays at 88C

I boot windows, it's stable, but struggling.

Long Version
So i bought a Corsair Hydro H115i closed loop watercooling system for my pc about 6 months ago, i installed it and it worked flawlessly up until a week ago when i started my pc and got CPU_FAN error as well as rapidly rising temps in the bios (never letting it go past 80c before i turned it off)

I plugged it into alternate fan ports, CPU_Opt, CPU_OV aswell as a different power slot and made sure everything was plugged in correctly and got the same result. I assumed the worst; the pump had died.

so i uninstalled the cooling system and took the train to "NetonNet" the electronics store where i bought it to try to use the warranty. i left the cooling system there for their judgement and was told they'd message in a few days.

a week later i got curious and dug up my previous cooling system, a Corsair Hydro H110i which had started giving me high temps but still worked OK when i last uninstalled it. i installed it in my pc, and got CPU_Fan error once again with rising temps i the bios, this time however i let the temperature climb higher and it stayed at a stable 88 C

I booted up windows to see how it would perform, fans got really loud and corsair link showed temps of about 95 - 99 c but it didn't crash or anything. The backside of the motherboard to where the CPU is installed is warm enough that i get burned if i put my finger on it for more than a second or two

Started it up a second time now and installed core temp, it seams my CPU temperature stays the same 95-100 c regardless of CPU load, however it seams to be compensating by slowing down.

i use arctic silver 5 and it is applied correctly.

My specs are

Motherboard: ASUS Z97-PRO [WI-FI ac]

GPU: EVGA Geforce GTX 980

CPU: Intel core i7 4790k

Powersupply: EVGA supernova 750 G2

Cooling: Corsair Hydro H115i alternatively Corsair Hydro H110i





 
Solution
That error means that the pump isn't turning. When the CPU temp gets that high under little to no load, it also takes out the thermal paste. When it reaches that temp under load, there's a temperature drop between the CPU die and the paste. Under no load, the two are almost the same temperature, and thermal paste usually doesn't like 100C.

The other way to tell if the pump is off is to see if the top of the pump is hot. If it is, the pump isn't turning.

I would recommend checking the fan profiles for the machine to make sure the CPU_FAN header is set to 100% and PWM mode. Also, make sure that the pump is plugged into that header.
That error means that the pump isn't turning. When the CPU temp gets that high under little to no load, it also takes out the thermal paste. When it reaches that temp under load, there's a temperature drop between the CPU die and the paste. Under no load, the two are almost the same temperature, and thermal paste usually doesn't like 100C.

The other way to tell if the pump is off is to see if the top of the pump is hot. If it is, the pump isn't turning.

I would recommend checking the fan profiles for the machine to make sure the CPU_FAN header is set to 100% and PWM mode. Also, make sure that the pump is plugged into that header.
 
Solution