Is my AIO cooler failing?

[ValkyrieStar]

So, on the new year i bought a Threadripper 1950X & accompanying Aorus X399 Gaming 7 motherboard.

 

I initially had an Asetek style cooler, which was simply unable to get the heat away from the CPU (because it's got a small coldplate). So i upgraded coolers and bought a Liqtech TR4 360mm cooler. Temps were insanely low! 4 months on however, temps are now at the point where i'm concerned about either the cooler or the CPU.

Using my 24/7 OC setting, i tried Prime95, temps quickly shot up and the system ended up shutting off for overheat protection! Odd, considering i used to be able to bench easily at 4.2ghz 1.4v.

I reverted clocks back to stock (and reflashed the BIOS just in case), and the temps were still high, reaching the temp throttle point of 68c within seconds (even my Asetek one didnt perform that badly!)

 

Loading up a reference point overclock setting (3.75ghz @ 1.275v), i was getting 86c, considering i originally was getting 58c at that same setting when originally fitted, that's a 30c increase! WHAT?!

 

Temps are ~30c higher than when orgiginally fitted?

 

I immediately stopped the test and reapplied paste, oddly the paste had turned a slight tinted green colour (the enermax stuff that came with the cooler), but was otherwise still similar to how it was when applied. I reapplied the same stuff in the same method (4 x 1 inch stripes where the dies are) and got exactly the same results, obviously the green tinting had nothing to do with it.

 

Is my cooler failing or is it my CPU? or something else?

 

FYI readings from original and current were both taken using the same version of HWinfo64 with the Tdie reading. I understand Tctl is artificially 27c higher so i ignored that.

 

Original Results;

 

Current Results (3.75ghz @ 1.275v, same profile as Slight OC of original)

 

[ValkyrieStar]

To answer my own question, I opened it up (after confirming that i could still return it with the vendor) and found some quite disgusting residues (see pics)