A2000 PSU fan replacement

[alenppc]

I thought of replacing the whole A2000 PSU with an AT one, but sadly the holes and the mounting screws on the back of the case do not match... So I guess I'll just replace the fan, because I can't stand the noise of the original.

Is it safe to replace the A2000 PSU fan with a quiet low-rpm one? In particular, I am talking about the Cooler Master Ultra Silent 1400 RPM. I have been successfully using it in lots of AT power supplies over time, but I am not sure about that old A2000 beast. Should it blow towards the inside or the outside the case?

[orange]

one hole matches, you have to drill just one more, its easy.


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I'll try to make some more that are relevant.

I think it should blow outside.
if your fan is very noisy it could be already rotating at low rpm, I'd say its safe to use that new fan.

[Zac67]

Depending on the degree of extension of your A2k, the fan may or may not move enough air. Well expanded system require at least 40 m³/h, heavily expanded ones even more.
The fan pulls hot air out of the case, note the direction of the original one.

[orange]

I noticed that newer fans are better designed (smaller motor), they have larger 'wings' so it would seem to move more air with each rotation..

[amigakid]

It is not a good idea to take apart a PSU.  I work on networks and computers for a living and this is never a good practice, even unplugged they still store power in them.  Best and safest thing to do is to replace the whole PSU with a new one.  You can always figure out a way to mount one that doesn't fit correctly, but please rethink messing inside the PSU

[alenppc]

amigakid wrote:
It is not a good idea to take apart a PSU.  I work on networks and computers for a living and this is never a good practice, even unplugged they still store power in them.  Best and safest thing to do is to replace the whole PSU with a new one.  You can always figure out a way to mount one that doesn't fit correctly, but please rethink messing inside the PSU

Thanks everyone for their replies... I am well aware of the risks involved, and I am extremely careful what I touch inside the PSU. I have replaced countless dead fans inside various AT/ATX units so I know what I'm doing, but thanks anyway. :-) I also usually let the PSU sit unplugged for at least 48 hours before opening it.

The problem with AT power supplies (at least the ones I've got here) is that not only the screw holes do not match, but also the power plug and fan are on the opposite side, which would require heavy modification of A2000's back plate which I am not willing to do.

Anyway, I will try to replace just the fan and see how it goes.

[cv643d]

You could remove the fan and mount an 80 to 120 mm fan adapter and an 120 mm fan. Mount the fan adapter and the fan externally.

[orange]

oh you mean AT PSU. I was referring to ATX one. Why not use ATX, they are newer. If you do, don't forget they are mounted upside down.

[alenppc]

I wanted to use an AT PSU simply because I have about 5 or 6 unused ones I picked up from Computer Recyclers, and I have no ATX ones which I would have to buy...

Anyway, I replaced the fan inside the original PSU and so far it looks good. I still have to reassemble the whole unit in order to test it properly, but the airflow is close to the original (especially considering the original fan was 20 years old!) and you can't hear a sound coming from it.

I also got the 1MB Agnus (8372A) from Vesalia, but sadly it does not work properly. I get graphics corruption all over the screen when moving windows and stuff, and the Amiga appears to be considerably slower. I have no idea why this happens... When I put the original Agnus 8370 back everything returns to normal. So I guess I am stuck with 512K chip... Oh well :-(