GeekwormCooling Fan Expansion Board (X728-A1) for X728 & Raspberry Pi 4 Model B/ 3B+/ 3B/ 2B

Be aware that this does not work by itself, and only works as an add-on to the main power management unit..

Keep Raspberry Pi 3B+ temperature under control in remote continuous application, for more than 3 weeks now and counting. Although the exact autonomy without power supply has not been fully tested, the set-up allows for disconnecting the power supply for more than 3.5 hours without interrupting operation of the RPi application.

I don’t usually write reviews, but I felt compelled to with this product. There is an abundance of documentation that you can reference, which made the setup process incredibly easy. Every aspect of this UPS is well thought out, and it’s refreshing to use a product that is so well designed after being disappointed by the product offerings in the past.

The Geekworm PI Cooling Board (X728-A1) dropped the stress test temp of a non overclocked PI 4 by 25* C degrees in an 81* F room! It went from running @ 75* C to 50* C. It also dropped the idle temp from 47* F to 38* F! When the stress test was complete the temp returned to 38*C very fast. This is with the cheep heat syncs installed that came with my CanaKit. Very impressed.

Using the included 2.5 x 20 mm standoffs created an initially annoying problem. The 40 pin header extenders I have were about 6 mm too long, making the UPS float way above the Pi and preventing the stackup from fitting in the Geekworm metal case. I first trimmed down the pins on the header extender. That didn't get the UPS board low enough to fit in the metal case. I finally trimmed down the plastic on the header extender, that dropped the UPS by another 2 mm and solved the problem. Nowhere do they mention that a non-standard-height 40-pin header is required to get the stackup to work in the case. That was kind of annoying.Second annoyance is the "ac power" input. Where/what is this? The UPS board doesn't take ac power. So I'm guessing that it's the 5521 jack?As well, why would that jack be rated for only 5 Vdc? This should be designed to take a wide voltage range (10-30 Vdc would be great) that that I could power it in the truck without having to custom build yet another 12 to 5.1 stepdown converter.Other than these significant annoyances the UPS seems to work fine. I haven't yet installed the software to enable the autoshutdown feature. Since this is for the truck, I appreciate a UPS to prevent glitches getting to the RPi.