Power Tower PSU question

[lurkist]

I`ve been without my beloved A1200 for over a month now(aarrghh)! I`m waiting for a replacement PSU.  Just wondered if anyone knows, is the PSU in Power Computing`s Power Tower just an unmodified AT PSU?  Could I just buy a generic AT and attatch the converter cables?

Cheers.

[x56h34]

Yes, it is a standard AT power supply. If you can't find a new replacement, perhaps you can buy an ATX to AT power supply converter cable with a power switch connected to it, and use a good ATX power supply with your Power Tower.

[Ianoakley]

There should be no problem with replacing like for like however AT power supplies are not that common.
Best way forward is to buy an ATX power supply and fit and ATX to AT convertor as supplied by Amigakit (product code ADAPV003).You will also need an ATX power switch (PWRATTXSW1) which can be fitted behind your existing Power Tower on off switch.

There are two advantages with this way forward:
 1. it future proofs your power supply and
 2. you can get a power supply with a beefier output

[lurkist]

Thanks both, I was beginning to suspect this was the way, and in fact checked it out on Amigakit.  My only concern was that the Power Computing AT-Amiga cable may be non-standard.  It may be the time to cancel my Power Computing order...

[Ianoakley]

The Power Computing AT Amiga cable - is that the lead that plugs into your Amiga and then you connect the P8 & P9 connectors to the power supply.
If that is what you refer to that item remains however the plugs are connected to the convertor instead of the AT power supply.
If you get a Mediator 1200LT you ditch the Power Tower lead as the P8/P9 attach to that unit.
Works a treat!!.

[lurkist]

Finally got my replacement PSU today after 6 week wait.
It was not an original Power Tower AT as advertised, but an ATX with the ATX-AT converter.

It does not work.

AAAARRRRRGGGGGHHHHHHHHHH!

It has a power switch leading straight from the ATX connector, fits perfectly behind the Power Tower switch.
When pressed, the power and HD lights flash then go out, no power, no indication that the PSU is on (no fan noise).

There is a strange 4-way plug (in a square shape, not in a row) with yellow and black leads which connects to nothing I can see in the Power Tower.  Presumably it fits on a PC mobo.

The Power Tower has a Standby button on the front with leads connecting to the little board you get with a P.T. that fits on the floppy power / LED ports on the 1200 mobo, but this switch has never done anything in the past, and still does nothing now.

No instructions were included, no AT-Amiga lead (lucky I didn`t bin the old one, eh?), no monitor pass-thru (not essential, just one more gripe to add to the lengthy list).  Power Computing have let me down for the last time, I think.  I only went for this purchase as it was advertised as the original P.T. replacement PSU and it`s not.  I could have (and should have) got this set-up with the proper power I.C. board from Amigakit for less, more quickly, and frankly better service (the one and only Amiga specialist at Power Computing seems to keep very random hours).

Incidentally, I got the delivery comfirmation (for 2-3 days) 5 1/2 weeks ago!!!

/end of my longest ever post/rant.

[amigagr]

lurkist wrote:
Power Computing have let me down for the last time, I think.  

back in 1/2001 i order from them AmigaOS3.9 CD and 32mb for the a1200. after 5 months of wait and a lot emails and answers from my side, i cancel the order from the bank a reorder the cd from Schatztruhe germany. i never trust them again for anything (PowerComputing)

[Ianoakley]

I assume the ATX convertor is similar,if not the same, as that sold by Amigakit whereby the ATX lead from the power supply plugs onto the converter and the P8/P9 plugs from the Amiga complete the circuit. If the power switch is attached to the converter it should work - that was my set up before I purchased a mediator.
Might be worth testing with another power supply.

What a pity Power Computing's standards regarding the Amiga have stooped so low. I've ordered lots of stuff from them and have had no complaints regarding the service. Mind you my last order was a few years ago. However compared to Amigakit there is no comparison and their service is excellent.

Hope you get this sorted !!

[lurkist]

OK, the story gets stranger.

If nothing is connected but the floppy drive and front LEDs, the ATX works.  As soon as I plug anything else in and try again, it doesn`t.  This applies to the hard drive, the CD-Roms, and the Amiga mobo itself.  Defective ATX?

[Ianoakley]

Bet you wished you'd stuck with your AT supply however I presume everything worked with that !!

With the floppy / front led solution does the Amiga boot?
Also when you try the HDD and CDROM is that with the floppy also connected. Try each component individually and see what happens. Make sure the AT P8/P9 connectors are the right way round. Also try without the blizzard.
The easiest test is the ATX power supply if you've got a PC.
I've spent many hours fault diagnosing and whilst it's a pain it's the only way to get to the root of the problem.

[lurkist]

-Bet you wished you'd stuck with your AT supply however I presume everything worked with that !!

It was dead.

With the floppy / front led solution does the Amiga boot?

No, literally just the LEDs worked, if the Amiga was plugged in - no power.

Also when you try the HDD and CDROM is that with the floppy also connected

Yes

Make sure the AT P8/P9 connectors are the right way round

They were.

Also try without the blizzard.

I never introduced the Blizzard into this setup for testing, too risky.  If it was going to work, it would have worked with a stock A1200.
I only wish I could have disconnected my scandoubler for testing as well, but it`s soldered in there after my first run in with P.C. when they would not replace the socket that fits over Paula when it proved to be too loose to connect  (see another thread).



I spoke to P.C. today, there is a possibility that they sent me the ATX-Amiga for an A4000 meaning the pinouts were wrong.  Luckily the power cutout was kicking in and not frying my motherboard.  Someone brought in an AT and they will be sending me that straight away.  I will have to send back the ATX costing around £5-6, bringing the total to around £50.  Not sure if the AT will be 2nd user / refurb job.  If so, they will not be getting the ATX back at all unless they compensate me accordingly.  (they don`t know this yet!)

It is a great shame, I have been a constant customer of P.C. since 1998 and have bought dozens of items totalling almost a £thousand Sterling.

Off topic, my woes continued today as I tried to buy a bag of compost for a gardening project with a voucher that had 3 years left on it.  They would not take it as they no longer dealt with the company issuing the voucher!
They say bad luck comes in threes... NO, DON`T EVEN GO THERE!!!!!

[lurkist]

The saga continues-
When he said he was sending me the "correct part" I assumed he meant an AT PSU, what he sent was another ATX-AT cable.  The identical one.  After some extensive testing last night it seems that the +5v part of the PSU was working, but the +12v was not (at least, when the floppy and front LEDs were connected the PSU worked, but not with any other devices or the Amiga).  They are now sending me another PSU (yes, another ATX).
I'll keep you posted.

[lurkist]

New ATX has arrived from P.C. and exactly the same problem.  This surely cannot be a coincidence, am I doing something wrong?  I think not.  Does anyone know what the square 4-way connector is that I spoke of earlier?  By the way, the motherboard is confirmed working with a weedy PSU and just to be double sure I disconnected everything (long and annoying process) and tried another mobo - same thing.
Insult to injury - I have bought another PSU (an AT from eBay) and it is overdue with no comms from the seller.  How much bad luck can one guy have?!

[amigakit]

Simon: Do you need just a PC generic AT PSU with P8 and P9 connectors?  I'm sure I have a used one here- when I find it, you can have for nothing- just pay P&P.

[tonyvdb]

Hi Lurkist,

Maybe this will help. Here is the pinout voltages for the ATX power supply if you place a jumper across pins 14 and one of the other ones (just cant rember what one) and that will power it up so you can test all the pins.