Reply 20 of 29, by TheMobRules
ykot wrote on 2020-08-16, 13:42:Did you measure the time it takes to heat the heatsink from room temperature and operating "stable" temperature? Because there are multiple parameters to watch for (that is, the whole temperature curve), not just some temperature at some random point of time.
I had this aluminium foil (I don't think it's graphite) on my Deschutes P2 as well and several socket 370 heatsinks too, but in practice I've found it not so good for heat transfer. Before removing the foil, you could do a very simple test yourself - disconnect the fan and power up the PC and measure how quickly the external heatsink becomes uncomfortably hot for your hand to touch. Then, remove the foil and instead apply thermal paste, but not just at the place where the foil was, but either at the whole surface or at least in multiple large spots, then repeat the test. This is subjective but very effective test - the difference in heat transfer is so big that you'll notice difference without using a thermometer.
With the fan working this was difficult to notice as the heatsink only gets mildly warm, so I agree it would have been a good idea to do some tests without the fan, unfortunately I only thought about that after I had removed the pad...
ykot wrote on 2020-08-16, 13:42:I think this aluminium foil was used not much as a replacement for thermal pad, but as a softer surface to avoid damaging CPU's die, before manufacturers started to use integrated heat spreader (IHS) somewhere around P3/Tualatin time.
If you look at my picture you'll notice the heatsink surface is really rough, so maybe they thought the pad would provide a smoother surface for contact.
swaaye wrote on 2020-08-16, 15:34:I found the Intel Thermal Design Guidelines for Pentium II SECC1. It's clear their preferred TIM is paste, but suggest a thermal pad might be adequate too.
http://datasheets.chipdb.org/Intel/x86/Pentiu … II/24333102.PDFI imagine a pad is the cheapest, easiest cooling option for the assembly line.
That document has a lot of interesting info! Thanks!
auron wrote on 2020-08-16, 17:28:all klamath and most SECC1 deschutes didn't have exposed dies, it's just the pii 450 that had been moved to flip-chip packaging afaik.
Right, as I mentioned above even some 450 P2 like mine (SL2U7) are of the "older" type, without the exposed die, where the heatsink actually contacts what Intel calls the "thermal plate" in the document posted by swaaye.