How to upgrade an Amiga 600...
Modifying the Apollo
The Apollo is a good card but suffers from some design tweaks and above all from tremendous heat problems. As little as the card is, it produces enough heat to kill the chips on it within a few hours (especially the fast versions). Without some modifications it is therefore not advisable to use the Apollo for a long time and probably even impossible to do so because it will either die or become unstable. The problem is made worse by the design of the Apollo which comes with a plastic shield put on top of the processor (!) which is supposed to hold the A600's internal hard drive. This makes cooling impossible as no fan or heat sink will fit between this and the processor.
That is why the Apollo MUST undergo some modifications before it should be used -- at least if it's supposed to live longer than a few hours or days. The following picture shows what happens if you do not cool: The dead 68882 FPU from my Apollo after two hours of uncooled run time:
The main issue is cooling. The other is power. The Apollo consumes more power than a regular A600 PSU can deliver, making it even more unstable. Add memory, a hard drive and probably even an external disk drive and you will hardly see the Amiga finish booting without
crashing (See the PSU section how to resolve this
The solution: The Apollo needs to be glued onto the A600 / the mainboard, once the configuration you have is stable. We have used "Panzerkleber" which you better don't touch once it's been put onto something. Make sure you use a glue that doesn't get liquid when heated up and isn't chemically aggressive, killing the processor or some circuit paths.
Before inserting the Apollo or in case you encounter stability problems, try and bend the pins of the socket that is put on top of the 68000 carefully inwards using a needle or similar. Be careful not to break one of the pins! Do not use too much force. Cleaning the pins with ispopropyl and / or a tooth brush might be a good idea as well.
To further stabilize the Apollo's supply voltage solder an electrolytic capacitor (100uF/25V, watch its polarity!) and a ceramic capacitor (100nF, type X7R) onto the PADs on the left hand side of the Apollo. Those were supposed to be used as a connector for an additional power source. The Apollo however gets all power it needs from the 68000 socket. On the picture you see the capacitors on my Apollo. The small, brown capacitor in the middle is the ceramic capacitor. The yellow capacitor on the righthand side is an additional 100nF ceramic capacitor which however you don't necessarily need.