Quote from: MrTeal on December 16, 2013, 04:03:12 PM

Quote from: GenTarkin on December 16, 2013, 03:45:51 PM

Quote from: ChipGeek on December 16, 2013, 01:58:13 PM

Quote from: GenTarkin on December 16, 2013, 06:35:01 AM

can someone tell me which parts of the VRM are most important to cool w/ little heatsinks?

It's best to just add heatsinks to the back of the board. However, the parts you are cooling are the black plastic transistors between the large aluminum cylinders (the filter capacitors) and the large black cubes of metal (the inductors).

The reason the back is better to cool than the parts directly is that the parts are mounted with a metal pad in the middle that is designed to conduct the heat into the board. On the other hand, the top of the part is plastic and does not conduct heat as well. Thus, cooling the back of the board is best. Also, when you add heatsinks on the top of the parts, you risk shorting out some of the other small capacitors near the devices you are cooling.

To repeat: It is best to heatsink and cool the back of the board under the VRM, and NOT heatsink any of the individual parts.

can you take a pic of what area on the back to add heatsinks to?

The copper around the fets is pretty efficient at transmitting heat, so using a bigger heatsink interface is always better than a small one since the thermal resistance of the solder mask and whatever adhesive you use is actually quite high. As a bonus, there's a couple areas that you can use to help cool the inductors if your HS is big enough to cover them.

Awesome, thanks for the pic, which heatsinks would well for those areas? links to any would be awesome =)