hmm, I dunno. Seems a little strange to me. Sure the i7 can idle down 300MHz below the i5, but I have a hard time believing that would make a significant difference. At load, the i7 ought to pull more power 45W TDP vs 35W for the i5, so the i7 should create higher temps. Although you said you reapplied TIM a year ago on the i5, its possible that you did a better job this time?
If you're going to ask it that way, anything is possible
, but not too likely. The HSF came off the old cpu with a thin, clean, even coat.
I'm having trouble finding detailed documentation on the speedstep states for the mobile Sandy Bridge i5s vs. the i7s, but if the slightly lower frequency also allows a slightly lowered voltage, that could make a large difference, since power scales linearly with frequency, but exponentially by voltage (in simplified terms, P = V^2 / R). And yes, it puts out plenty of heat under load.
Also, was this just a straight CPU swap? Did you have to reinstall Windows or anything of that nature for the system to accept it?
Straight swap under Windows 10 Pro x64. Didn't even re-activate. The only thing I did first was issue a shutdown from the command line to ensure it didn't go into hybrid shutdown, then wake up angry.
shutdown /s /f /t 0
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