core i5 4670k throttling at 4.2GHz 1.15Vcore

Giroro

Splendid
Last night I was attempting to increase the overclock on my core i5 4670k which was what I believed to be stable at 4.2 GHz, hoping to get it up to 4.4Ghz or 4.5.

I noticed when running Prime95 that the temperatures would hit 95-100C and the frequency would drop from 4.3Ghz within a few seconds and within a couple minutes settle with the cores near 3.9 - 4.0. Going back to the old 4.2Ghz configuration it behaved about the same.
I set voltage to "adaptive mode" at 1.15V, which the ASRock overclocking app would show go up to about 1.18. Switching to override mode didn't seem to make a difference. I know a lot of OCs on this board are closer to 1.25V but that seemed like a bad idea with things already so hot.
Normally when gaming temperatures are usually ~70C and my PC idles 8-10C above ambient.
Is my cooler inadequate? Is there a way to improve this without buying a new cooler? Or what kind of cooler would be better? It looks like space might be a limiting factor if I go too big.

Cooler: ZALMAN CNPS9500
Case: APEX PCV-588 Black Steel ATX Mid Tower Computer Case (5 fans)
Mobo: ASRock Z87 PRO4

Reapplying thermal compound (MX-4) didn't seem to do very much, maybe dropping idle temps by about 1C but I've been thinking about delidding for fun, regardless.
 
Solution
From what i know that cooler design is a bit old.
Probably old thermal paste under ihs can do that but thats alllll up to you if you wanna to do it.
If you want good all round cooler Cryorig h7 is your choice. They have on official forum how to make model if the cooler can fit. Its usually around 50$.
Cheaper option is Hyperx 212 evo.
From what i know that cooler design is a bit old.
Probably old thermal paste under ihs can do that but thats alllll up to you if you wanna to do it.
If you want good all round cooler Cryorig h7 is your choice. They have on official forum how to make model if the cooler can fit. Its usually around 50$.
Cheaper option is Hyperx 212 evo.
 
Solution

Giroro

Splendid


I'll take some measurements, but If I can't get a 120mm tower cooler to fit, how would it compare to say, a closed loop cooler with a 120mm radiator?
 

Giroro

Splendid
I bought the Cryorig h7 which ended up being $35. It works better, now running prime95 my pc will stay at 4.3GHz for about 20 seconds before throttling when it would only last about 2 seconds before. It's still a little disappointing to see a cooler rated for 140W have trouble when my hardware monitor is telling me the power draw is closer to 100W. The air coming off the cooler isn't even particularly warm.

So I'm going to delid. I have a feeling Intel's TIM has probably dried up at some point over the last 5 years. I found a $8 chinese delidding tool that looks like it will work, plus the cost of liquid metal TIM although using my Mx-4 would probably be good enough if its an aging issue. $50 all-in seems like a worthy investment if it means I can delay a platform upgrade until intel reaches 10nm or at least they get some hardware security fixes... or DDR4 prices start going down.
Worst case, I was already prepared to upgrade everything before trying all this.
 

Giroro

Splendid
I haven't tried AIDA64.
I did delid yesterday and applied conductonaut - which is a pain to work with. I accidentally applied too much the first time and it was not easy to remove. It was otherwise not very hard to do. If I hadn't been using liquid metal it would have taken less than 10 minutes.
But, wow it made a huge difference. The old thermal compound was a little annoying to remove because it was no longer a paste. It had gone hard and was the consistency of a pencil eraser, which is scary-bad. I essentially had to scrape it off.

I went from throttling at 100C within a few seconds on prime95 small fft to a steady state temperature in the 80-85C range with no throttling at 4.3GHz. The idle temps went down a couple degrees but that at that level there wasn't far to drop.

With as bad as that thermal paste had gotten, I'm convinced that was my primary problem. I think anyone still using a Haswell processor should seriously consider performing a delid as necessary maintenance, even if you use a normal thermal paste.