Nepton 140XL, CPU Temps Climbing to 100°C

[Bludude41]

So I recently upgraded my rig from a Z97 system to an X299 setup:

Intel i7 7800X

Gigabyte X299 UD4

Corsair Vengeance LPX 3000MHz DDR4

 

and I just used my Nepton 140XL that was previously cooling my Z97 setup and bolted it onto the X299 setup.  I've had this cooler for over 4 years, and even though it's a "sealed" unit, I'm pretty sure that over the years some water has evaporated because as I was remounting the radiator, I heard the water sloshing around like there was a good amount of air in the system.  So I bolt everything up, and I have Core Temp running on my taskbar tray just to be sure, and after a while, my temperatures start climbing from 60°C, to 70, 80, it hits 100°C, and my chip starts throttling down to 700MHz.  Now when I unplug the fan and pump from their headers and re-plug them back in, the temperatures go back down to ~40°C - 50°C, which (with what I have running) seems about right where they should be.

 

I'm not sure if the pump is dying, or if it's because there's air in the system, but I can't have these temps go up to T-Junction like that.  Should I try popping open the CLC and adding water to it? If so, is it distilled water that I add? Should I pick up some antimicrobial additive or something? Any/all help is much appreciated.

 

Thanks!

 

-Bludude4

[Fasauceome]

4 minutes ago, Bludude41 said:

I'm not sure if the pump is dying, or if it's because there's air in the system

probably both, an older worn out pump can't force air bubbles through as easily. If you want to try your hand at exchanging the water yourself, it's worth it. Had an old asetek cooler I did this with and it helped a lot.

[Bludude41]

So I pulled off the "Warranty Void if Removed" sticker on the radiator fill port, pulled out the old coolant (which had a greenish tint) and put in some distilled water. It was a PITA, had to use a syringe, and tip the radiator every which way between shots because it would shoot right back out the port if I didn't. After I got it completely filled, I hooked it all back up, and the temps kept climbing. That's when I noticed the light on the CPU block, where the pump is.  Upon boot, it would be lit up, but after a while, the light would dim, then go out.  Not sure why, because I had it plugged into the fan header labeled "CPU PUMP". But I noticed that not long after the light on the block goes out, that's the temps skyrocket. So I plugged it into the molex-powered fan header in my Source 530, and the light is now staying completely lit up all the time, and my temps are staying around 32C at idle. Have yet to burn it in, but if anyone else decides to get a X299 UD4, plug their Nepton 240XL into their CPU PUMP header not touch the BIOS fan settings. and are wondering why their chip is hitting T-Junction, it's because your pump is turning off. 

(I tried plugging the pump into the "SYS_FAN1" header and it was still turning off. Whatever, I fixed it.) Thanks for the advice @fasauceome!

 

EDIT: Ran IntelBurnTest, maxxed out the chip for a hot minute, and the temps only went up to 65C, which is waayy less than 100. Yaaayyyy!!