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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: fragment on January 24, 2009, 04:40:09 PM

Title: A3000 without -5V ?
Post by: fragment on January 24, 2009, 04:40:09 PM

My PSU in my A3000D is dying and needs a replacement. Unfortunately many new ATX PSUs do not have the -5V line. According to the A3000D schematics it is connected to the external video port and the Zorro/ISA slots.

I have one slim ATX power that would nicely fit in the case but the problem is I do not know if it will work. Does the A3000 need the -5V for something else as well? And will Deneb work without it?

Title: Re: A3000 without -5V ?
Post by: DoogUK on January 24, 2009, 04:51:51 PM

This page might be useful to you.

http://www.ianstedman.co.uk/Amiga/amiga_hacks/Amiga_Power_supplies/amiga_power_supplies.html

Title: Re: A3000 without -5V ?
Post by: fragment on January 24, 2009, 08:42:15 PM

It is very good for general information but unfortunately does not answer my questions.

Title: Re: A3000 without -5V ?
Post by: DoogUK on January 24, 2009, 09:07:52 PM

i always thought the -5v was supplied along the grounds.


According to the guide -5v IS present in atx supplies

Title: Re: A3000 without -5V ?
Post by: fragment on January 24, 2009, 09:16:29 PM

It became optional since ATX revision ATX12V 1.2 therefore not all ATX PSUs have it. (And after v2.1 the -5V was removed completely)

Title: Re: A3000 without -5V ?
Post by: DoogUK on January 24, 2009, 09:39:58 PM

Ahh i see....what about using an AT supply instead? would solve all your problems.

Title: Re: A3000 without -5V ?
Post by: fragment on January 24, 2009, 09:47:51 PM

Not all, first I would have to find one that will fit nicely in the case  :-)

Title: Re: A3000 without -5V ?
Post by: DoogUK on January 24, 2009, 09:51:08 PM

I've seen a few people on a2000's have stripped the original parts out of the power supply case and replaced them with AT/ATX's, i'm not familiar with 3000's but could that be an option for you?

Title: Re: A3000 without -5V ?
Post by: fragment on January 24, 2009, 10:00:06 PM

Sure, but most of the AT/ATX PSUs are too big for their insides to fit inside the A3000 PSU which is quite small.

Title: Re: A3000 without -5V ?
Post by: adolescent on January 24, 2009, 10:02:36 PM

http://www.amiga.org/forums/showthread.php?t=39419

Sounds like the -5V is just for the ISA slots.

Title: Re: A3000 without -5V ?
Post by: fragment on January 24, 2009, 10:26:47 PM

Thanks! I had missed that thread. Gonna try without the -5V then..

Title: Re: A3000 without -5V ?
Post by: DoogUK on January 24, 2009, 11:27:18 PM

let us know how you got on!

Title: Re: A3000 without -5V ?
Post by: fragment on January 25, 2009, 05:32:59 PM

It seems to be running nice and stable. Now I just need to attach the PSU properly, attach the AC plug in the back of the case, add a 80mm case fan and connect the power button nicely  :crazy:

A photo of what it looks like at the moment. (http://fragment.fi/kuv/a3000_atx_psu_fitting.jpg) Mmmm, Dell. I lost a drive bay but that isn't a big issue.