Amiga 1200 won't power on

[ArcadeGuru]

Hi all,

Just fitted a SCSI adaptor to my Blizzard 1260. Plugged everything back in and powered up. Nothing from the amiga just a whining sound coming from the power supply. Unplug the SCSI card and the Amiga powers up fine. My guess is the power supply hasn't got enough juice to run the 1260 and SCSI card together? What do you think? Anyone know where I can get a decent power supply? I guess I am after an old A500 one but I would prefer a new one.

[Buleste]

I agree the PSU hadn't got enough oomph a common problem when adding the SCSI kit to a Blizzard. It's either try a 500 PSU or see if you can do one of the numerous convertions of PC PSU's.

[ArcadeGuru]

Cheers Buleste. I can confirm it's PSU. I have a Blizzard 1230 which I attached to the SCSI and installed in the Amiga. It powered up fine. Guess the 1260 uses a bit more juice Time to find a A500 supply then !

[Harrison]

Have you been using the standard 23W A1200 PSU up to this point? If so, I'm really surprised it managed to run even a Blizzard 1230 as I've never got one to do that without crashing, so wouldn't have expected an 060 board to have at all.

I use something called a Golliath PSU. These were made as after market PSUs for the Amiga and are 250W PC PSUs in an external case with an Amiga power cable. I bought it back in the early 90's after buying my first A1200 and it has been perfect ever since.

You can fairly easily convert a PC PSU to run as an Amiga PSU. Most people cut the existing Amiga Power cable from the under powered A1200 PSU and use that to wire up to one of the 4pin Molex connectors on a modern PSU. You would then need to hardwire the soft reset wires together in the 20/24 pin motherboard connector of the PSU to it powers on as son as the PSUs main power buton is switched, and that is it. Fairly easy to do. Just need to then find an external enclosure to put it in.

AmigaKit.com and amigamaniac.com both make and sell conversion cables to make this whole PC PSU conversion process even easier if you did want to consider it.

Others have also taken an existing A500 PSU apart and fitted a small PC PSU inside, so it looks like you are using a real Amiga PSU, but in fact it could be a 400W PC one. The CA member StuKieth did this recently and he posted some pics on the forum if you have a look.

[ArcadeGuru]

Thanks for the info Harrison. I have it running fine with just the blizzard card using a 25W A1200 power supply. I bought this new from Amigakit a couple of years ago before I had the intention of adding hardware.

I have sourced an old A500 supply. This outputs 4.3amps at 5V and 1amp at 12V as opposed to my current one which outputs 3.0amps at 5V and 0.1amp at 12V. Do you think this will be enough? I won't get it till Wednesday

[Harrison]

You sadly won't know until you get it. Some A500 PSUs seem stronger than others, even though they are meant to all be the same. One of mine will power my most kitted out A1200 perfectly well, whereas another doesn't.

And a note for anyone else. Avoid A600 PSUs at all costs as they are weaker than even A1200 PSUs and adding even just a 2.5" internal HDD to an A600 can cause trouble.

[ArcadeGuru]

My mate has an A600 and I did consider asking him. Glad I didn't now !

Spoken to AmigaManiac who is very helpful and can point in the right direction. Have one of his ATX adaptor cables on order Luckily I am breaking a PC and the PSU will be spare so I intend to use this. Luckily it's a silent PSU which is good news Just need to think of a way to bolt it down on to something.

[ArcadeGuru]

Just an update for anyone who's interested. Received my A500 PSU which runs at 60W, 4.3A at 5V and 1A at 12V Plugged it all in and hey presto the Amiga powers up fine. PSU dosen't even get warm. Still going to run it of a PC PSU but nice to know I have a backup.