Sorry about the delay. Here is what I came up with:
Test Platform:
Core i7 920 D0 (Mine is a leaky chip that runs at low volts but at high temps)
EVGA Classified 759
Mushkin Ascent DDR3 2000
PC & Power 1200W
Windows 7 64
Thermalright Extreme 120 Rev B (lapped)
Thermalright Extreme 120 Rev C
Ambient Temps 23.2 degrees Celsius
As usual, Thermalright's boxing job is top notch. No changes here on the newest revision.
Here is what was in the box:
Here is what the new mounting looks like. I only snapped pics of it on a 775 platform. 1366 looks the same.
I had a few more pics but dunno what happened to them. Pretty much you have the two metal pieces that hook to the backplate by 4 screws. Then you have the metal piece that goes thru the heatsink and is held down by two screws instead of the four screws of the previous versions.
Now time for testing. I'm not going to go into hours and hours of testing. Just some quick ones.
First off we have my Rev B Lapped at idle.
Now stressed.
Now the Rev C idle.
Uh oh. As you can see I am a good 5 degrees hotter at idle with the Rev C than the Rev B lapped. That is where my Rev B was before I lapped it. So pretty much this tells me the cooling is about the same so I won't go into anymore testing as it is clear as can be. I pretty much figured this would be the case as the surface on the Rev C is the same as before. Curved like no other. Thermalright states they do this on purpose but too many times people have lapped theirs and gotten better results. I am walking proof as stated before my Rev B was 5 degrees hotter until I lapped it. Just for giggles I hooked my Rev B lapped back up but with the new mounting from the Rev C and I was back to regular temps. So the new mounting has no significance over the old except ease of installing.
So if you are looking to update your old TRUE thinking you will get better results, don't. The only thing you will get is easier mounting.