Upgraded CPU. Reaches 100C within 2 seconds fan won't go full speed

Dogoid · 11 Sep 2019 at 15:46

Got a used I7 4790k to replace an i5 4690k , notices in game and benchmarking temps go to 100c near instantly so i reseated fan, same thing. Went into BIOS and enabled fan to be full at all times, still fan ( stock i5 cooler ) wont rev up past 2100RPM.

with i5 i had no probs with temps , load 65-70C.

I am using the i5 stock cooler with the i7 BTW.

orbitalwalsh · 11 Sep 2019 at 15:50

https://www.overclockers.co.uk/alpenfohn-brocken-eco-advanced-cpu-cooler-120-mm-hs-05j-al.html

an0nym0us · 11 Sep 2019 at 16:00

Dogoid said:
I am using the i5 stock cooler

Is your current cooler something like this?

If so, that stock cooler is almost useless.

As suggested by orbitalwalsh, you need to upgrade to a better CPU cooler.

Dogoid · 11 Sep 2019 at 16:10

Yes it is, but it was great with i5, and before i get another cooler i want to rule out defective die temp sensor etc. my CPU fan wont go full speed even at 100c

an0nym0us · 11 Sep 2019 at 16:19

The 4790K runs quite hot. If it were me, there's no way I'd consider using the Intel stock cooler with that CPU, even if the fan could ramp up to higher RPM.

Danny75 · 11 Sep 2019 at 16:24

The stock cooler never handled those i7s well at all.

That said, press down on the four corners of the cooler while you're running a bench, see if temps decrease at least a bit. Could be an issue with one/some of the mounting pins after removal and re-mounting, quite common.

Which motherboard is it and how much Vcore is it giving the chip?

Finners · 11 Sep 2019 at 16:30

I brought a used PC once with a haswell i7 in it like yours and it had a AIO cooler with a failed pump.

I fitted an air cooler and it would still run really really hot. I ended up delidding it and it was fine after that. I assume that having been used with a failed cooler and bouncing off the thermal limit for who knows how long it had cooked the paste under the heat spreader and the only way to fix it was to replace it.

EsaT · 11 Sep 2019 at 16:59

Likely combination of crappy Intel buzzaw with its crappy mounting, possibly broken/worn because used, and possibly Intel's bubblegum/toothpaste under heatspreader going bad.

Something like this would be huge upgrade:
https://www.overclockers.co.uk/raijintek-aidos-direct-contact-cpu-cooler-hs-002-rt.html

Dogoid · 11 Sep 2019 at 17:20

EsaT said:
Likely combination of crappy Intel buzzaw with its crappy mounting, possibly broken/worn because used, and possibly Intel's bubblegum/toothpaste under heatspreader going bad.

Something like this would be huge upgrade:
https://www.overclockers.co.uk/raijintek-aidos-direct-contact-cpu-cooler-hs-002-rt.html

just might get that, cheap enough. cheers.

LuckyBenski · 11 Sep 2019 at 18:10

If it's getting to 100 in less than 10-20 seconds there's no way the heat is reaching the heatsink.

What does it do at absolute idle? Do the temps drop down quick? Slow? How far?

Almost certainly a delid job, even if that cooler reaches 100° it should take a minute or so to do.

The fan issue doesn't sound good either though. Do speeds change at all? Snip the 4th wire for maximum speed. The blue one.

Dogoid · 11 Sep 2019 at 18:51

No speeds don't change with fan at all stays 2100RPM. When i bench and leave it for a bit putting my fingers on the heatsink isn't that hot.

It gets 100C in 2 seconds.

Temps go down very fast yes.

Tried SpeedFAN, can't even manually alter fan speed. Just ON/OFF Software controlled or Smart guardian.

LuckyBenski · 11 Sep 2019 at 19:50

Definitely sounds like heat isn't making it to the heatsink. As above double check for bad cooler mounting. I'm assuming you cleaned and repasted the chip/heatsink?

Dogoid said:
Tried SpeedFAN, can't even manually alter fan speed. Just ON/OFF Software controlled or Smart guardian.

In Speedfan for me (Gigabyte Z97X-SLI) I set the PWM1 fan to "software controlled" and check the "remember it" box. This enables the Speedfan control to actually work. Took me ages to figure out.

Dogoid · 11 Sep 2019 at 20:03

Put the i5 back in now, and temps aren't as erratic. Not shooting to 100c like the i7.

Alsone · 11 Sep 2019 at 22:00

Dogoid said:
No speeds don't change with fan at all stays 2100RPM. When i bench and leave it for a bit putting my fingers on the heatsink isn't that hot.

It gets 100C in 2 seconds.

Temps go down very fast yes.

Tried SpeedFAN, can't even manually alter fan speed. Just ON/OFF Software controlled or Smart guardian.

Sounds like an issue with the i7. Maybe there's a thermal paste issue underneath the lid. No CPU should go to 100C in 2 secs if it's thermally cooled on boot. I take it you're using the both paste for both CPU's and following the manufacturers recommended application method for each type of cpu. Another thing to beware is lifting the heat sink as you apply it as this lets air between the paste and cooler and air is a very good insulator.

For temp comparison, my current pc uses an i3770K. At boot I'm on 28C max and in use around 33C with a Max of 40, all on the Intel stock cooler.

Rroff · 11 Sep 2019 at 22:04

Does sound like a problem with the thermal interface somewhere but can vouch those stock Intel coolers don't handle a i7 4790K - my brother has (or had not 100% what he has right now) and it practically overheated with his older stock cooler of that style so he stuck it under water cooling.

Those 4790s are boosting well above 4GHz so get hot quick.

d_brennen · 11 Sep 2019 at 22:12

Those push pin Intel coolers are pretty crap to be fair and the mounting system isn't great for repeated removal. Check the plastic pins are still in good shape and that the paste is actually being spread over the die by mounting pressure alone

d_brennen · 11 Sep 2019 at 22:14

Rroff said:
Those 4790s are boosting well above 4GHz so get hot quick.

I have a few HP SFF systems at work with 4790S in them. Very small box and pretty much the same style cooler. No idea what temp that run at but they are only barely audible when really working hard

Rroff · 11 Sep 2019 at 22:18

d_brennen said:
I have a few HP SFF systems at work with 4790s in them. Very small box and pretty much the same style cooler. No idea what temp that run at but they are only barely audible when really working hard

It is weird, though maybe somewhat down to soldered v rubbish TIM, but my 4820K has a far higher TDP than the 4790 yet I've had pretty much no temperature problems versus my brother. He is also using a SFF case with I believe a GTX1060 currently and external watercooling which kind of defeats having a SFF setup.

Grafter67 · 12 Sep 2019 at 04:55

Take it off, redo the paste and reseat it. That is beyond blaming the hardware.

pastymuncher · 12 Sep 2019 at 09:49

When I bought a used 4790k I couldn't even get decent temps using custom water with the radiators being cooled by outside air. When I delidded it the Intel thermal paste had set like concrete and coverage was patchy at best. Once cleaned up, liquid metal applied and the IHS refixed I got a massive 25 degree drop in temps so I would probably bet that something similar has happened to yours.

It should be noted that the 4790k never came with a heatsink and being a hot running cpu the i5 heatsink is never going to cool it adequately. ***Edit*** It appears that some SKU's did have a heatsink but I am pretty sure the OCUK page for the retail cpu stated that it didn't and my used retail one didn't have one either and I did have all the packaging for it as well.