Better thermal pad or paste under the compute module
Replace the ~4 mm stock pad, which is sized for the A-06, with a thinner high-quality pad or paste that matches the real CM4/CM5 gap.
What it takes
- Disassembly
- Purchase required
Difficulty 2 of 3 — moderate.
Details
The pad that ships with CM4 kits is about 4 mm thick while the gap to the shell is nearer 3 mm, so it compresses badly and transfers heat poorly. The thread settles on a thinner pad such as Thermal Grizzly Minus Pad 8, or thermal putty, cut to the SoC.
packetwanderer's CM5 build tested HY910, Gelid Extreme and Fujipoly 15 W/mK compounds on the hotspot areas with the same reasoning. Measure your own gap before ordering — it varies with the adapter board.
Links
Open at Forum threadRelated mods
Two layers of 0.5 mm thermal pad and a small aluminium heatsink on the CM5 SoC, held with thermal tape — about 10 °C cooler under load.
A CM4 socket protection adapter lifts the CM5 so a 0.5 mm pad reaches the back shell instead of the thick stock pad.
A ~3 mm copper block bonded to the BCM2711 so a 0.5 mm pad can bridge the remaining gap, adding thermal mass.
A 40-pin FPC ribbon from the mainboard's GPIO connector to a breakout board gives a fan its 5 V and ground inside the case.
The adapter board's PWM fan header runs a Raspberry Pi, Waveshare or EDATEC CM5 cooler; printed back covers make the room.
A cheap magnetic gaming-phone cooler clipped to the aluminium back pulls heat out of the whole console when a CM5 is working hard.