Something different this time. I've been doing a lot of software and AI stuff lately, so here's a couple of hardware projects I've been meaning to talk about.
#Performa PSU Replacement
I had two old Macs with dead power supplies: a Performa 630 and a Performa 6200. Both are mid-90s machines and the original PSUs are proprietary, so finding replacements is a pain.This involves rewiring mains voltage - live, neutral, earth. Get it wrong and it can kill you. If you're not confident working with mains electricity, don't do this.
I spent a while digging through forums trying to find a modern PSU that would work. First I bought a Corsair SFX unit that turned out to be too big. Eventually I found the FSP FSP270-60LE(80) - about seven quid on eBay. It's compact enough to actually fit, puts out the right voltages, and has built-in protection for overheat, short circuit and overvoltage. Watch out for fakes on eBay though - the genuine ones have the fan on the same side as the ATX connector.
The main work was adapting the power input to the new supply, then soldering up the power loom I removed from the original PSU and wiring the 6-pin adapter from the old supply to the ATX connector on the new one. I followed this guide on 68kMLA for the pinout, but people in the forum suggested using a 2N3904 transistor for the soft power circuit instead of a 74LS04 inverter IC. There's an open source PCB design based on that approach, but it doesn't physically fit inside the PSU case so I just wired it up by hand.
The Performa 6200 powering on with the new PSU - you can tell I was pleased
Both Macs are running again now. The Performa 6200 has become useful as a test machine for PeerTalk, a cross-platform networking SDK I'm building for Classic Macs. I've got it networked with MacTCP and running LaunchAPPL - a tool from the Retro68 project that lets you deploy and run apps on old Macs from a modern machine. More on that in a future post where I'll be using it for automated performance testing.
#PS3 Thermal Paste Replacement
My brother's PlayStation 3 was running hot and loud. The original thermal paste dries out over time, so I stripped it down and replaced it.
Stripping down a PS3 and replacing the thermal paste
Lots of screws and ribbon cables, but nothing too difficult. Just take your time and keep track of what goes where. Tested it with Fallout 3 and Red Dead Redemption before handing it back - runs much cooler and quieter now, and I managed not to start another playthrough of the Mexico chapter.