8700k core issue...again!

greenbrucelee · 23 Mar 2020 at 23:13

Back in the summer of 2017 I bought an 8700k from overclockers which was delidded etc and capable of 4.9GHz after 12 months a couple of the cores were getting to 100C whilst the rest stayed at acceptable temps (about 70C). Overclockers took the cpu back and re-did the delid and things were ok. Tonight one of the cores is hitting 100c whilst the next highest core is 70C when running the benchmark on shadow of the tomb raider.

Has the delid gone wrong or something?

Specs are

8700K
Fractal celcius s36 AIO
Fractal r6 case
asus maximus x hero
32GB corsair dominator 3000MHz
corsair 960 NVME
Corsair 1TB SSD
WD Caviar 2TB platter drive
Gigabyte Aorus 10Ti

doyll · 24 Mar 2020 at 12:09

Considering history and assuming load is same on all cores it seems logical. That said, do you know what tim OcUK used?

greenbrucelee · 24 Mar 2020 at 12:37

doyll said:
Considering history and assuming load is same on all cores it seems logical. That said, do you know what tim OcUK used?

I don't but I assume it was thermal grizzly. I'm going to take the cooler off and reapply paste (grizzly) and see what happens

I'm not confident enough to do the stuff underneath

EsaT · 24 Mar 2020 at 15:01

With pretty small contact area and different thermal expansion of CPU die and heatspreader paste might be getting pumped out.

doyll · 24 Mar 2020 at 15:20

greenbrucelee said:
I don't but I assume it was thermal grizzly. I'm going to take the cooler off and reapply paste (grizzly) and see what happens

I'm not confident enough to do the stuff underneath

Indeed! Much easier to R&R cooler / waterblock and determine if tha'ts the issue.
It's a long shot, but it could be cooler related as well as TIM set IHS to AIO and/or chip to IHS, although being just a couple of cores makes it most likely CPU chip to IHS .. meaning delidding to fix. S36 pump has MTBF of 50,000 hours so about 5.7 years runnng 24/7 and I think is rated for only 40 L/h so not a lot of flow even when new. But coolant level top up is bigger possible issue as it does slowly leak through hoses .. especially if rad is in bottom or front with fitting at bottom of rad. Where is radiators in /out fitting in reference to CPU block/pump? Could install a 'T' fitting in hose with another hose off of that with capped end to use to top up coolant level. Ideal is having pump below top of system so any air in system is not trapped in pump but in radiator.

Edit: What EsaT said is my first guess too. But re-seating AIO is much easier. Once you know IHS to AIO is not problem, we can figure out how to go about deal with chip to IHS. Maybe a member who knows how to do it lives near you.

greenbrucelee · 24 Mar 2020 at 17:09

EsaT said:
With pretty small contact area and different thermal expansion of CPU die and heatspreader paste might be getting pumped out.

doyll said:
Indeed! Much easier to R&R cooler / waterblock and determine if tha'ts the issue.
It's a long shot, but it could be cooler related as well as TIM set IHS to AIO and/or chip to IHS, although being just a couple of cores makes it most likely CPU chip to IHS .. meaning delidding to fix. S36 pump has MTBF of 50,000 hours so about 5.7 years runnng 24/7 and I think is rated for only 40 L/h so not a lot of flow even when new. But coolant level top up is bigger possible issue as it does slowly leak through hoses .. especially if rad is in bottom or front with fitting at bottom of rad. Where is radiators in /out fitting in reference to CPU block/pump? Could install a 'T' fitting in hose with another hose off of that with capped end to use to top up coolant level. Ideal is having pump below top of system so any air in system is not trapped in pump but in radiator.

Edit: What EsaT said is my first guess too. But re-seating AIO is much easier. Once you know IHS to AIO is not problem, we can figure out how to go about deal with chip to IHS. Maybe a member who knows how to do it lives near you.

I'll try new paste when I get the chance. I work in care so pretty full on at the minute. Hopefully I have the day of tomorrow so will try then. Will keep you posted

doyll · 24 Mar 2020 at 17:17

greenbrucelee said:
I'll try new paste when I get the chance. I work in care so pretty full on at the minute. Hopefully I have the day of tomorrow so will try then. Will keep you posted

Anything I can do to help just give a shout. You might be albe to activate your 'Trust' account ('trust' button lower right of each post) and send private email to other members with accounts.

greenbrucelee · 24 Mar 2020 at 21:22

doyll said:
Anything I can do to help just give a shout. You might be albe to activate your 'Trust' account ('trust' button lower right of each post) and send private email to other members with accounts.

for some reason it doesn't work. It's says to enter the password used to login but says its wrong.

I'm not sure what to do as I highly doubt overclockers will take the cpu back and fix it again. It was just out of warranty the last time. I can't afford a new cpu either at this moment in time.

greenbrucelee · 24 Mar 2020 at 21:48

I have sent a webnote to OC UK to ask what they can do but I think they may be shut for a while because of covid19

greenbrucelee · 25 Mar 2020 at 17:31

EsaT said:
With pretty small contact area and different thermal expansion of CPU die and heatspreader paste might be getting pumped out.

doyll said:
Anything I can do to help just give a shout. You might be albe to activate your 'Trust' account ('trust' button lower right of each post) and send private email to other members with accounts.

No answer from overclockers I think they are maybe shut because of covid 19. I wonder if I was to just get a new CPU what should I get? Although I'd rather this cpu gets fixed as it was pretty expensive.

greenbrucelee · 25 Mar 2020 at 17:36

Just had an email they are going to let me send it back to them again.

doyll · 25 Mar 2020 at 18:56

Sounds like good customer support. If it's same problem as last time, maybe back the overclock down a little so it doesn't run quite so hot.

greenbrucelee · 25 Mar 2020 at 19:50

doyll said:
Sounds like good customer support. If it's same problem as last time, maybe back the overclock down a little so it doesn't run quite so hot.

It's supposed to be guaranteed to do 4.9. my temps usually idle at 28-34c and under full load 76c is the highest I've hit.

greenbrucelee · 26 Mar 2020 at 13:01

doyll said:
Sounds like good customer support. If it's same problem as last time, maybe back the overclock down a little so it doesn't run quite so hot.

I spoke to them on the phone today they think its a delidd fail and said they have a new method which should ensure it doesn't happen again. I loaded optimised defaults to see what the temps are like at default and core 1 is spiking to 85c and core 3 to 65c whilst just using the internet then dropping back to normal then spiking whenever I do anything. Package temp is reading 95c when it spikes, havent dared putting a game on. I've got an RMA and will post it off tomorow.

greenbrucelee · 1 Apr 2020 at 10:22

doyll said:
Sounds like good customer support. If it's same problem as last time, maybe back the overclock down a little so it doesn't run quite so hot.

CPU is on the way back to me. Delis had failed. Apparently the new method OC UK use to delid means the paste doesn't dry up so everything should be ok. Will keep you posted

greenbrucelee · 2 Apr 2020 at 14:44

doyll said:
Sounds like good customer support. If it's same problem as last time, maybe back the overclock down a little so it doesn't run quite so hot.

got it back. seems to be ok. I'd run out of thermal grizzly so used NH-T1 paste. Hopefully it will be ok. I'm running optimised defaults at the moment will leave any overclocking until I monitor the temps