Sega Dreamcast – picoPSU, Battery Holder and Controller Fuse Mods

Last summer I modded my Dreamcast with a GDEMU and Noctua fan; I decided it was a good time to throw in a few more mods: a new power supply, battery holder, controller fuse and a 3D printed insert for the GDEMU.

Replacing the original power supply is generally recommended when you remove the optical drive to install the GDEMU or USB-GDROM; supposedly the power supply runs hotter because the 12 V rail is no longer loaded by the optical drive. There are a few ways to go about replacing the Dreamcast power supply:

I found an eBay seller offering pre-modded picoPSUs for the Dreamcast; they even include a 3D printed bracket to secure the unit in the same place as the original power supply. I went with this option since it was the most complete solution and required the least amount of work.

A 12 V DC power adapter is also needed to drive the picoPSU. Most recommendations are for one that can output 2 A to 5 A; you can find tons of generic wall warts and power bricks that meet this criteria on Amazon and eBay. I wanted the best one so it was hard deciding which of these generic power adapters to buy. Luckily I found a Seasonic power adapter that works perfectly for the Dreamcast picoPSU mod: the Seasonic SSA-0601HE-12. It’s rated for 12 V 5 A and has the correct barrel connector for the picoPSU (2.5mm, center positive). Seasonic is known as one of the best PC power supply manufacturers; based on Seasonic’s reputation alone, I’m going to say that this is the best power adapter for the Dreamcast picoPSU mod.

Installing a GDEMU leaves a lot of empty space in the drive tray and SD cards can drop out of reach during swaps. I bought a 3D printed insert that fills the void and came with an SD card extender; the insert gives the Dreamcast a nicer look and makes it easier to swap SD cards. The insert can be purchased from this eBay seller.

Years ago I modded my Dreamcast to use eneloop batteries instead of the built-in rechargeable battery. It works but doesn’t seem to last as long as you would think despite the capacity being several times greater. I removed the eneloops and installed a button cell battery holder and ML2032 battery for a cleaner look. I ordered the holder from Amazon and the battery from eBay but you can also find them bundled together on eBay like this.

The Dreamcast suffers from a common issue where controllers stop working because of a blown fuse although mine has never had this problem. I replaced it anyway with a PolySwitch 72V 400mA fuse from Amazon. This fuse can be reset by turning the Dreamcast off and on again. It’s a simple mod to perform; just swap the old fuse (labeled as F1) on the controller board with the PolySwitch. You can find a detailed guide on this mod here.

This is now the coolest Dreamcast I own; the only thing it’s missing is a DCHDMI. Fortunately I’ve already got a VGA box and OSSC.

macOS Mojave – Reset and Lock Size of Dock

I like keeping the macOS Dock at the default size but sometimes I fat-finger with the trackpad and accidentally resize. It’s a shame there is no obvious way to change it back to the default. Fortunately someone figured out the default value of the dock size; you can restore the size with the following command:

You can also disable resizing entirely with:

 

Logitech G900 Battery Upgrade

I found an upgraded battery for my Logitech G900 mouse and it has been working well for the past 2 months. The new battery has a capacity of 1000 mAh vs the original’s 750 mAh; it does seem to last longer on a single charge even though the Logitech Gaming Software still reports the same amount of running time (in my case, 25 hours with my lighting settings). The software is probably hard-coded for the original 750 mAh battery; I’ve noticed when the mouse is down to 20%, the software will continue to report there is 20% remaining for a few more hours before it continues to drop.

Opening the G900 is fairly straight forward; there is one T5 Torx screw by the micro-usb port and six 00 Phillips screws under some of the feet. I highly recommend purchasing a set of replacement feet rather than trying to reuse the ones you pull off. Be very careful when opening the G900 after removing the screws; there is a delicate ribbon cable connecting the two halves of the mouse as you can see below. You’ll want to disconnect the ribbon cable from the bottom half so you don’t accidentally rip it when you work on disconnecting and removing the battery. The battery is secured with double-sided tape so it will take some time to pry it out gently. The replacement battery has much longer leads but with some care it will all fit back inside.