PC ATX Powersupply modifications

[JohnFante]

I have recently changed the PC ATX powersupply in my towerised Amiga 4000D. It uses a modifier like this to connect to the Amiga:

http://amigakit.leamancomputing.com/catalog/product_info.php?products_id=615

Unfortunately my motherboard died shortly after I replaced the powersupply. The original powersupply was a Enermax 300W and the new one a no name 500W. Apparently some resistors (and some more) on my motherboard was burnt and it could be caused by a dodgy powersupply. My old motherboard (I have bought a "new") was a bit dodgy so the error can be a combination of things.

However I am now looking for a high quality powersupply to use with the "new" mobo but I am a bit unsure what modifications I have to do. I could see that the original powersupply had one of the wires cut. See this photo:

https://dl.dropbox.com/u/139090/PowerSupply.JPG

I also did that with the new one. Is there any other modifications that I need to make? And are there any suggestions for top of the line powersupplys?

[Delta]

I use Antec TP-550 power supplies with digital recorders that are worth 5000$ each so you can go with this brand without worries.

And maybe this link will help getting some answers: http://www.ianstedman.co.uk/Amiga/amiga_hacks/Amiga_Power_supplies/amiga_power_supplies.html#Fitting_a_new_PSU_to_an_A4000

[JohnFante]

I use Antec TP-550 power supplies with digital recorders that are worth 5000$ each so you can go with this brand without worries.

And maybe this link will help getting some answers: http://www.ianstedman.co.uk/Amiga/amiga_hacks/Amiga_Power_supplies/amiga_power_supplies.html#Fitting_a_new_PSU_to_an_A4000

Thank you. I will look into the Antec powersuppy and the link.

At first I thought the converter was just more or less plug and play (with the addition of cutting a wire).

However after I burnt my old motherboard I got rather paranoid and I would like to be sure before I plug in the "new" mobo. One thing is 250 euro for a "new" motherboard but I would not like to thing of the possibility of frying my CSPPC ....

Anybody have any experience with this kind of converter?

[Delta]

I remember making the conversion from scratch on my 4000 long ago but it was an AT power supply, not ATX.  Never the less I used a voltmeter and checked every single wire BEFORE plugging anything.  

Make sure you get the correct voltage on each prior to connect, that's the best advice I can give.

[JohnFante]

I remember making the conversion from scratch on my 4000 long ago but it was an AT power supply, not ATX.  Never the less I used a voltmeter and checked every single wire BEFORE plugging anything.  

Make sure you get the correct voltage on each prior to connect, that's the best advice I can give.

I checket the current on my present powersupply.

It gives the following stable readings:

5V=5,17 volts
12V=12,21 volts
-12C=--11,45 volts

I am not sure if theese are "safe" numbers.  

Any comments?

[Delta]

Yes, voltage in power supplies is never perfect unless it is for sensitive electronics.

You can trust these values, its all normal.

[ElPolloDiabl]

I use a no name PSU on my PC at the moment and I can concur that the voltages are a bit off of what they should be.
I've used an Antec in the past. They are one of the better companies.
Just be careful of some of the companies that put their badge on a budget PSU.

If you have done the AT PSU mod, ATX is not that much different.
Double check things like: +5V vs -5V. I believe the 12V on ATX can put out a lot of amps so if you get something wrong, it will fry your motherboard.

I haven't modded for a while so can't help you atm. Ask some more questions here however...