I have now installed this heatsink 3 times, and so I'm getting a handle on how to do it well. First and third times were my own, and the second was a friend's. Follow the instructions that Alpha give, except for a couple of things: 1. It tells you to use 2 washers per spring screw. I have found however, that using 3 washers per screw gives much better results. They do say to do this if you want more pressure. All installs I've done have been in KT7A boards, so it might not be necessary for some other boards. 2. Once you've put the standoffs into the motherboard, mounted the heatsink to them and tightened all the screws down, hold the board vertically and tighten the screws further and you'll see that the standoff and nylon nut turn in the motherboard. Hold the nut still with your fingers, and tighten the screw, and that will tighten the standoff to the board, and provide a little more spring pressure also. 3. Before you mount the fan, don't forget to put the shroud onto the heatsink. However, to make things look better, and stay that way, peel the white tape-stuff off the shroud. I've heard that it gets all dusty and horrible anyway, and also if it isn't on there, the shroud can dissipate heat also. 4. Suck or Blow? The instructions don't actually say which way to mount the fan, although the pictures show it such that the fan sucks air out of the heatsink. However, I've found that I get better temps (ie lower) with the fan blowing into the heatsink. I suspect that this may depend on your case airflow, fan, etc. 5. Make sure that nothing wobbles. If the fan wobbles on the heatsink, check that the screw are tight, and that the shroud is fitted correctly. You may need to turn the shroud through 90 degrees. If the heatsink wobbles on the CPU core, apart from being worried about cracking the CPU, you should increase the pressure (see 1 and 2). 6. Sit back, and enjoy the finest air cooling there is. My PAL8045 puts many water-cooled rigs to shame (ie, I've attained a higher overclock from same stock level, for a lot less outlay on cooling (£50 total for my PAL8045 and 53CFM fan vs ~£200 for watercooler) and with reasonable noise levels and similar temps). Some of these points may also be applicable to the MC462 (like the stand-off tightening, and fan direction).
As an addendum to this little guide, I've now mounted my 53CFM mechatronics drawing air out of the heatsink, and the temperatures have not really changed. I previously had it blowing in, and prior to that I had a 45CFM YS-Tech drawing out. It seems that the temperature change between the two fans was pretty big, given the small difference in power between them. I wonder if the important point is not the CFM of the fan, but rather the static pressure it can create, given the dense pin-spacing of the Alpha. I am going to leave the fan drawing out, because that's how Alpha say it should be, and I reckon they're probably a little better at thermodynamics than I am... What I think this might indicate is that there's a threshold for the PAL8045 to become a performance heatsink with the right fan. You need something reasonably powerful to get the best performance, but with something like the mechatronics or a similar-spec Sanyo Denki or Sunon, you get that performance at a very acceptable noise level (no Deltas!!!).
