Power conversionRebuild shelfHand tools, works as-is
Heatsink
Also called heat sink, aluminum extrude.
Aluminum from a supply, a monitor, an amplifier, a set-top box. The thermal interface pad is single-use. Clean it off and use a proper pad or grease when you remount.
If you are new to this category
These parts change wall power into the lower voltage a device uses. A sealed supply with a label is the safer kind. An open board from a lamp can still be connected to the wall on the side that looks like low voltage. Isolated means the output is not electrically connected to the wall. If you are not sure, treat the output as live.
Read the label out loud: volts, amps, and the polarity symbol. Then measure. A number you remember from a similar brick is not a measurement.
Left: a brick. The label is your spec, and the plastic is the safety barrier. Right: a board taken out of a lamp or a charger. Unless you have checked that the output is isolated from the prongs, do not let it touch a project you will handle while it is plugged in.
Mains voltage. Line voltage, and the DC bus just after the rectifier, both kill. A disconnected cord is not a discharged supply.
Sheet metal and glass. Case steel, shattered platters, lamp glass, and magnet chips cut deeper than they look.
| What to look for | Usual figure |
|---|---|
| Mount | Note the hole spacing before you drill new ones |
| Isolated? | Some device tabs are live. The mica or silicone washer was doing a job. Do not toss it and then bolt a live tab to a grounded case. |
Volts are electrical pressure, amps are how much current is flowing, and ohms are how hard the part resists that flow. A higher voltage than the part was built for is how salvage parts die on the bench. If a cell in the table says “read the stamp”, that stamp is the whole specification.
What people actually use it for
- Anything that gets hot
- A small aluminum plate
Leave this one when
It is anodized in a way you cannot mount to, or it is a laptop heat pipe (that is a different part).
Buying a new one is the better idea when
When the dissipation is calculated and this chunk is obviously too small.
How to tell if this one still works
Flatness against a straight edge. A bent sink does not touch the package.
Tools you will want: Screwdriver, Isopropyl.
Words on this page
Short meanings, so the rest of the entry is readable if you are not already doing this every weekend.
- isolated
- The low-voltage side is not electrically connected to the wall. A proper brick usually is. Many cheap lamp boards are not.
Where people actually find it
1 notes, most useful first. “Leave it” means the part is in that machine and you should not take it: it is dangerous, worn out, or only useful if you already know that exact repair.
| From | Call | How many | How often | Where it sits |
|---|---|---|---|---|
| Desktop PC | Worth it | 1–2 | usually | CPU, sometimes chipset or GPU. |
- In this particular machine
- Aluminum or a heat pipe on a copper plate.
- Where to look
- CPU, sometimes chipset or GPU.
- How to get it out
- Release the retention. Clean the paste. Do not cut a heat pipe.
- The condition to expect
- Reusable if it is not bent.