80C from just 35W? Yikes.
Well, it *is* a 12-inch laptop, the entirety of heat exchange goes through a 1x1.5x7 centimeters radiator on the end of a single heat pipe. Measuring the old fan I have around... Quite slim at 70x70x7mm.
80C is the *core* temperature, the case rarely ever heats up to 40C.
On the plus side, it only becomes audible at highest speeds. Cannot be controlled by SpeedFan, set to keep CPU temperature at ~45C and only has four speeds: off, 2600rpm, 3000, 3600. I suppose the liquid bearing would be destroyed if the speed was too low.
Still I keep it propped up on an eraser.
P.S. How did I end up using a laptop as my main desktop PC?
Because its very convenient, always having everything at hand.
the big danger was if the heatsink was poorly mounted or got pushed or something.
Ouch >_<
...
But even properly installed, it could eventually overheat and die in a case of a fan failure, possibly cooking other components.
Plus, I was using a fan salvaged from some old soviet printer, it ran on 220V, so I had to use a relay controlled by the +12V rail. Was a quite chtonic setup, the rattling beast installed in a hole i cut in the side of the case acted both as the CPU fan and the case fan, with nothing attached to the heatsink itself.
Because that was the era of short-lived 80mm fans and I had *enough* fans rattling and requiring urgent replacement every 3 or 4 months (every fan, dammit!). So I solved that radically.
But who would shut the system down in case of overheat if that single-point-of-failure fan stopped? The mobo couldn't be avare of my 220V fan and neither it or Windows had anything like "if oferheats, shut the hell off!" options, only SpeedFan was capable of doing that.
I experimented, finding the setup could run on passive cooling for a few minutes while Windows 98 was finishing swapping before finally reacting to the shutdown command.