copper Don't use Prime95 for Haswell, I don't think it has been updated properly (yet?) and it causes most systems to pull extra volts (and extra heat). The current recommendation is Aida64. Also make sure when you're stress testing, that your volts are set manually to prevent programs like Prime95 from pulling extra volts. Auto, adaptive, offset or any similar non-manual setting will let Haswell pull extra volts for the new instruction sets.
It's not the TIM, it's the space. This
member "Idontcare" from AnandTech forums is the only person I have seen test the spacing and the pastes. Unfortunately his Photobucket bandwidth has run out already for July so you cannot see his graphs. The short version is as follows:
"
the benefits of delidding are entirely due to the resultant reduction in gap height between the CPU silicon die and the underside of the IHS." He's even shown on Ivy Bridge that the Intel TIM beats TIMs like NT-H1. If your IVB or HW happen to have a smaller gap from the IHS to the chip, you will have better temps.
Like I previously said, the smaller the infrastructure the more heat. As the transistors shrink, the power draw doesn't keep pace. i.e. half the size doesn't mean half the power nor half the heat. So more transistors packed into about the same space, add IVRM and IGPU without the transistors' power draw matching their size reduction, that's more heat.
I know people go all crazy with ZOMG IVB and HW can't overclock like my SB 2600K, but because of improved IPC, they don't need to. Depending on who is doing the testing, HW is 9% faster than SB on single threads and 13% faster on multi-threaded tasks at the same speeds (obviously smaller improvements compared to IB). How many 2600K can hit 5Ghz? Not many. How many 4770K can hit 4.5Ghz? Most with comparable cooling... and that's equivalent for multi-threaded and they will do it with less volts.
The "dog" 4770K chips can do 4.3Ghz which is about 4.7GHz to 4.8GHz for a 2600K/2700K or 4.6 to 4.7GHz for a 3770K.
Awesome 4770K chips will hit 4.8GHz, the average is about 4.6GHz on 1.25 volts which would be a 2600K at 5.2GHz on at least 1.45 to 1.52 volts.
*EDIT Feb 2014 * - My experience is 4.5GHZ core / 4.4GHZ cache on 1.255 volts with 2400MHZ speed ram
Probably could get more core with more volts and less cache, perhaps less RAM speed, but this gives me a well rounded machine. Idle 30 C, Gaming 55 C, Stress testing 80-90 C
TL;DR - don't get Haswell if you have IVB or SB, you won't notice the difference.
I on the other hand, currently have a Q9550... I'll notice the difference :) To match the i5-4670K at 4.6GHz (I don't have HT currently) I would likely have to overclock to 6.9GHz!
