After reading here for quite some time, I though I´ll post my experience here aswell.
I bought 3 different i7 4770k on Amazon (during a 3 week period). I tested them all (temperature-wise) with a Corsai H80i (pull-push).
The first 4770k was decent concerning the temperature, but terrible on overclocking. With a 1.34v vCore I only reached a measly 4.4GHz clockrate. Still, unter IBT and Prime I never had it throttle (most of the time it was at around 90-95 degrees), with AIDA (and AIDA is a joke for temperature testing) I never even got above 80.
The second CPU was terrible, couldn´t go past 4.3GHz (even with 1.34v applied).
The third one was the win.....1.2v made it boot into windows at 4.6GHz. I managed to run it stable at 4.6 and 1.24v vCore and a 4.4GHz uncore (default Voltage). But gosh, the temperatures were terrrible. I could not run IBT or Prime, no matter what, even at a clock rate of 4.2GHz it throttled within seconds, reaching 99° on pretty much all cores. I ran it at 4.2GHz with a voltage of 1.18v and it still would throttle at 99 degrees.
After some consideration abouth what might be the best de-lidding method I went with the vise method. Poped in the Chip, put a tower over it, used a wooden block and gave it 4-5 hard whacks....and off it goes. On a NOTE: Everyone considering a delid....go with the vise method, it is friggin fool-proof!
I noticed that the die was not fully covered with termal paste by Intel...about a 1/5th of the die was blank, aswell as the IHS underside.
Well, I then used an old credit card to peel off the black silicone (you don´t need a dremel or any fancy tools, just use a creditcard...that black stuff will be so easy to get off with it). Took me probably 1-2 minutes to get it off, wiped it with some IPA, masked the capacitors with some electrical tape and covered the die with a VERY VERY thin coat of CLU. I did not applie CLU to the IHS, only to the die.
I then removed the electrical tape (I don´t think one has to mask the capacitors permanently, because CLU does not have any pumping effect that might dislodge any CLU on the die).
I then put the chip into the socket, put on the IHS and while holding it in place, I pushed the lever to close it. One important thing I noticed: Before delidding the CPU I had to push that lever insanely hard to make it close down on the CPU, but after delidding and removing the silicone it only took a quite light push (compared to before) to close it. I assume that silicone raised the IHS so much that I needed great force to close it. So, if anyone is having the same issue, a delid would most certainly help.
I mounted the H80i and used the Autotune 4.4GHz feature my Asus Maximus VI Hero comes with. The Bios crancked the voltage to a vCore of 1.25 (Adaptive). I knew this would result in a much higher vCore once IBT or Prime fired up (due to AVX), but I thought I´d give it a go.
Now: Forget all the idle temps postings....nonsense with that. Even with a part of the original thermal paste missing under the non delidded IHS my idle temps were in the low 30s (33-35). Still, I noticed a light bump on idle temps aswell, going down to 26-28 (my room is cool, about 19 degrees).
So, I fired up IBT and oh my god.....this was almost unbelievable. Even although the adaptive setting raised my vCore to 1.35v, the temperature was no higher than 68 degrees! Even after one hour of Prime95 the max temp reached was 69°!
After manually adjusting the voltage to 1.26v my 4770k now runs IBT and Prime95 at 4.6GHz at a cool 65 degrees max (remind you, cool room).
So, I might be one of the few that had a great chip, ruined by intel with a not proper thermal paste and IHS seating, but delidding reduced my temperatures by over 35 Degrees Celcius (most likely more, as before it would reach 99 and throttle).
So, if any of you guys have a chip that can boot into windows at 1.2v Vcore at 4.4-4.6GHz but fail to use it properly because it will start throttleing...please DELID
Thanks everyone here aswell! And yes, Haswell is great when delidded, but in my eyes, Intel screwed up the IHS seating big time!