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.

[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...

[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.

[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?

[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?!

[lurkist]

Amigakit - That`s a lovely offer, but I need one with a full set of connectors for CD-R, CD-RW, floppy and 3.5" HD.  I just thought the least troublesome way to replace a Power Computing Power Tower PSU would be with - quote "Original Power Supply Unit replacement for all our A1200 Power Towers".  Much appreciated, though.

TonyVDB - The unit(s) power up fine, just not with any load higher than a floppy drive.  Jumpering is not neccesary as the ATX-AT converter(s) have a push-on, push-off switch (confirmed working).  Plus I have no test gear!

Any thoughts on the 4-way square connector?  What is its function on a PC-mobo?

[lurkist]

It only works with a floppy drive and/or LEDs attached. NOT with CD-Rs or 3.5" HD (either standing alone or hooked to the IDE port).  It also works with the ATX-AT attached, and the AT-Amiga on top, but not with the mobo plugged in.  

It does seem like a short, but from where I cannot imagine, as all individual components are verified working.  The only thing I can think of is that the 4-way square could possibly need jumpering or something.

Sounds complicated I know, I dread speaking to P.C. AGAIN trying to explain the situation.  I fear that both PSUs are in perfect working order, but only when connected to a PC.  Their terms & conds state they won`t pay for return postage, so even if I get a refund I`ll be out of pocket and have had a 2 month delay for my troubles.

[lurkist]

PM`d.  This guy is a GOD!

[lurkist]

Here are the specs for the exact model(s) I had trouble with.  Maybe the more electrically inclined can spot any potential problems in the wiring.

http://www.enhanceusa.com/file/6_specification.pdf

[lurkist]

Posting this from my A1200, finally! WAYHAY!!

Extreme thanks to Amigakit whose donation of an AT PSU proved that all the gear was functioning correctly as suspected.

Power Computing have agreed to refund me, tails well and truly between legs.