A4000 PSU -> Mini-ATX PSU mod

[keropi]

After spending lots for a PPC A4000 , the old, weary 145W original PSU seemed like a ticking bomb to me, so I decided to use a modern ATX PSU for my 4000...
First thing to do was to order the following from amigakit.com , an ELBOX ATX-to-A4000 power converter (http://amigakit.leamancomputing.com/catalog/product_info.php?cPath=39&products_id=454&osCsid=271da26c95f6c3f8b9b513dae3b68b76) and an ATX Power Switch (http://amigakit.leamancomputing.com/catalog/product_info.php?products_id=418&osCsid=271da26c95f6c3f8b9b513dae3b68b76) for the converter.
I wanted to use the original power on/off button the A4000 has, and I thought: Why don't I use the original PSU's case? both their switches are screw compatible, so it was just a matter of opening the old PSU, removing the stuff inside, and screw the new ATX switch. Also the MINI-ATX PSU I got had the screws on the same place as the old PSU, so I just screw it in place... I did not use the whole A4000 PSU case, only the parts needed to support a 80x80 fan and the switch... with the atx psu screwed in place it is just a matter of inserting the old case in place, you will understand it better after looking at the attached pics... and all work nice, and very easy to mod! I only need to think how to cover the space under the MINI-ATX PSU (last pic) maybe I add a small fan blowing air inside...

[lopos2000]

Great mod keropi.
I think I'll do that on my A4000D next. Which Mini-ATX power supply did you use?

[keropi]

Thanx!

nothing special, a 300W one I found on a nearby computer shop... it also has a temperature controlled fan, so it is quiet...

[patrik]

Don't forget the psu lid, or else the cooling will be terrible (no air moving from entrance at Zorro-backplates through case, cooling all motherboard and Zorro+cpucard, into psu and out back).

Btw, make sure the big fan is blowing air out of the case, it was quite common that in some productions of the A4000, they were turned the wrong way, blowing hot air into the case from the psu, causing the A4000 to overheat.

This way it aquired its reputation as a overheater, which it really isn't as long as the fan is turned the right way and the cooling isnt screwed up by holes in the case on the cpucard side of the case, which would make the air only between hole and psu, not through entire case, leaving most of the computer uncooled.

[keropi]

oh, so I need to make it blow out of the case eh? it is a new fan, not the original... I'll do that, thanks for the remark!

also , what u mean by psu lid ?

[patrik]

Lid = top part of psu, to make the PSU closed, else it is impossible to get the PSU fan to blow air out of the case and create suction.

[keropi]

oh, you mean close it fully.... dunno about that, I was thinking of placing a fan on the empty space under the psu to help air escape...or maybe I just put back the side panel...

[patrik]

Closing the PSU and using the 80mm fan will be more effective and quieter than using a couple of small fans in the hole under the mATX psu. Also, with the PSU closed, the A4000 case will get more support, which it needs. It is not very rigid without everything in place, including the harddrive mounted with the brackets between the psu and the Zorro backplate.

Btw, with lid I mean the plate which is bent 90 degree in the middle, which gives the PSU a roof and one wall :D, I do not mean the back plate of the psu. The back part is fine open as there needs to be some way for the air to escape. If the hole under the mATX psu is closed shut, all air will have to go through the mATX psu which isnt that optimal.

[keropi]

ok then, I'll make a hole to the side panel so the power cables can get out... Thanks patrik!

[patrik]

If the cables are long enough, you could use the original cable-hole. Less work and that hole is fitted with the plastic cable-protector as a bonus :D.

[keropi]

bah, they are not that long... lol
also the hole is a joke, when your father owns a metal works factory... lol

[patrik]

Haha, ok :great.

[keropi]

Finally, the mod done thanx to Patrik's advice... I have cut the upper lid because the mATX psu had the same size as the amiga psu and it did not close good... now it has a seem on the front sice, but I don't really mind to hack more to fix it too... :blased ;) :nervous

[jmmijo]

Great job there keropi :great

I also liked the tips from patrik about closing the lid of the PS unit for proper air-flow, it's amazing how when you are doing a mod you forget about the details and the like ;)

[keropi]

I have sealed the seem with aluminum tape (used in ventilation)
it is like duct tape, only it is made from aluminum (duh!)

[macce2]

@keropi

Quote :

"First thing to do was to order the following from amigakit.com , an ELBOX ATX-to-A4000 power converter and an ATX Power Switch for the converter."

Is the Elbox ATX Power Switch necessary to get the ATX-to-A4000 power converter to work ..?

Recently, I bought the power converter from Elbox and planned to build my A4000D to tower case. I tried three different ATX power supplies, but none of them seemed to work with the Elbox a4000 power converter. I'm pretty sure I made the connections properly, although there surprisingly, came no any kind of manual/information with the converter package.
However, Should it work, when you put jumper on the power "switch" in the adapter ?

One of the three power supplies I tried with it broke, with a Baang!

[keropi]

you need an atx switch for on/off, that is similar to a reset switch, that just makes contact for a moment and then it goes back to non-contact...
maybe u tried a permanent switch, like the one on the 4000D psu or older AT PSU's ???

DON'T ever use a jumper there or an older 2-state AT style switch!!!! NEVER!!!

omg, is your 4000 mobo ok now????

[macce2]

So it needs some kind of pulse to start, rather than permanent circuit..?
I tried with a jumper, but to no avail. However, when one of the psus I tried blew up, there was no jumper.
I'm not sure yet, but I think that my 4000 should be ok.. (?)
I 'll check that thing tomorrow, because I can't say anything for sure about my a4000 funtioning just at the moment..

Do you think that my only option would be to buy tha power switch made by Elbox ?

I tried power switch button that was in my tower case, but I'm not sure if it is of the right type ..
It has some kind of "jumper" type connector connected to two wires..
so I thought it should work when I press the power button, but nothing happened :-(

[keropi]

u need a reset like switch to power on! or use a small screwdriver, touch the 2 pins for 0.5secs , it will power if all is OK... all it needs is an instantaneous contact, nothing more... amigakit also has those switches... don't try again the original 4000 power switch or a jumper...

[macce2]

I also tried with the reset button built in my new tower case, but it didn't help. I can't know for sure if the swich it's fully functioning, because the tower case was found, I didn't buy it ! ;-) But it was in good condition overall, I think. Shame that I can't send any photos about it, because I have no digital camera :).
Alas, the tower case I'm writing about is an atx case, I think, but I'm not 100% sure. However, I didn't use the power switch of my original A4000 D case !!

[macce2]

Thumbs up my A4000 motherboard is undamaged, I'll test it tomorrow..
Wonder if I 'll get any sleep tonight .. ;-/

[keropi]

good to hear that :spin

[P-J]

DON'T ever use a jumper there or an older 2-state AT style switch!!!! NEVER!!!

I've used a paperclip in the two pins on the ATX connector to fire up a powersupply without a motherboard (and left it in for the duration). Never done me any harm :)

I think it's all about PSU quality. 550w for £15 is likely to blow up in your face ;)

[macce2]

I'm very pleased to tell that my A4000 seems to still work ok. ;-)
I did eventually got the power adapter thing to work, thanks for your advice, keropi!
However, when I'm using the reset button of my tower case right now as a power switch, it seems to work ok, expect that it seems to be too sensitive for pressing. That means that I must hold the button very accurately, or else switching on the Amiga fails or alternatively, it just resets it, not switches it off, when you try to switch it off.
So, maybe you can tell me, whether the power switch made by Elbox is more easy to use ...?!

ps. sorry for my sometimes not so good English .. :-)

[keropi]

no, unfortunatelly even the elbox atx switch is not perfect... :(
it needs too accurate timing... sometimes the amiga will power on and after a second it goes off again, or reboots...
haven't found a solution to this yet... but then again my amiga does not work right now, lol

[macce2]

Ok, thanks for informing me again, keropi.

What's wrong with your machine, er..?
Gotta get back to continue work with my towering project!

Long live the Amiga ! ;-)

[keropi]

toasted csppc, ppc not working, sold it as dead, now looking for new one...
that sums it up :spin

[macce2]

That's very sad. I have already read so many times about broken ppc
accelerators, that I'm not very surprised. So, generally speaking, what's wrong with these Amiga ppc accelerators ? Why do they seem almost always get faulty at some stage ? I've never used one, but I must admit that for some time, I have been constantly dreaming about getting Cyberstorm ppc for my A4000 ;-).
I wish you best of luck in searching for a new one.

[keropi]

thanks, they rule...

[AMIGAZ]

That's very sad. I have already read so many times about broken ppc
accelerators, that I'm not very surprised. So, generally speaking, what's wrong with these Amiga ppc accelerators ? Why do they seem almost always get faulty at some stage ? I've never used one, but I must admit that for some time, I have been constantly dreaming about getting Cyberstorm ppc for my A4000 ;-).
I wish you best of luck in searching for a new one.

Problem is poor cooling fans which kills the PPC CPU, poor PPC soldering (DCE cards) and the 68060 can creep out of it's socket or the socket is very fragile so it breaks easiliy

[Zetr0]

Heys Guys

am i missing something, I am a little confused

Why not run PS_ON (pin 14 ATX) to ground (any COM) ? you can use a regular 2 state button. I have been using that method for years when converting AT psu's. There are sooo many Atx and Btx testers and they all us the same method to power on the PSU.

I have only need to ONCE create a pulse to draw circuit and that was on one VERY fussy and old ATX psu.

Here is a good guide
http://www.ianstedman.co.uk/Amiga/amiga_hacks/Amiga_Power_supplies/body_amiga_power_supplies.html

also has a simple circuit on there for pulse to draw. basicaly as long as there is a 1amp load on the 5v line a pulse will work when operating the PS_ON switch, It all works :)

its very simple..

[mrodfr]

toasted csppc, ppc not working, sold it as dead, now looking for new one...
that sums it up :spin

maybe you could send your card for repairing at amigacenter in france ???

[keropi]

@mrodfr :

nope, I sold it on eBay to a polish person that says his brother can repair it... personally I hate the idea of a 2-3 times repaired csppc, so I gave it in order to find another of, perhaps, better quality

[macce2]

Well, I think that my tower project has failed.. I found my used (and found!)
tower case far too small, cramped and shaky :-/ .
So , I'm going to buy used Mirage Pro PCI 4000 kit .. ;-)
Until then my motherboard will stay on it's orginal desktop case. (damn, it's so hot inside! )

[macce2]

@keropi

QUOTE:
" @mrodfr :

nope, I sold it on eBay to a polish person that says his brother can repair it... personally I hate the idea of a 2-3 times repaired csppc, so I gave it in order to find another of, perhaps, better quality "

- maybe that Polish guy could also fix my Cybervision64 card ..? :-)
(see my new thread in Marketplace section of EAB ! )

[mrodfr]

@keropi
- maybe that Polish guy could also fix my Cybervision64 card ..? :-)
(see my new thread in Marketplace section of EAB ! )

why not ask to amigacenter in france ????

[macce2]

@mrodfr

Maybe I'll do just that, thanks. :-)
How can I contact them ?

[keropi]

for future reference to anyone interested:

I could not run succesfully with the mATX mod my A4000D that had a csppc, grex4000D+voodoo3 . aga was dead and the amiga crashed when aga screenmode was active. It run OK only if the voodoo was not present or the ppc chip was "sleeping" by means of not installing warpOS or disabling powerpc.library . the amiga run perfect with the original PSU. :(
I tried 3 different mATX psu's with the same results... so this is not recommended for ppc amigas!

[alexh]

Bet you 50p I could fix it ;)

[CU_AMiGA]

would this work with me? i have a csmk3 and picasso iv soon to have a cvisionppc too. i could buy one off you keropi if your atx works on the uk electric current!

[keropi]

@alexh:

how? tell me an idea! there is a thread on .org with the symptoms... I have no idea what to do to make the atx work with my setup!

EDIT: now there is a person on the amiga.org thread (http://www.amiga.org/modules/newbb/viewtopic.php?topic_id=36496&forum=9) that had the same prob, apparenthy it is caused by the g-rex, he now uses zorro busboard+cvision with atx without probs....!

@CU_AMiGA:
I think it will work on your setup, there must be some strange power draw when the ppc is active together with the voodoo that draws much power...
if you are still interested I have a new mATX psu (250W - +3,3v@16A, +5v@25A, +12v@13A, -12V@0.8A ) that you can have for 20eur shipped to UK (as much as I got it) All Europe electric stuff are 220-230v, only the plug is different in UK , so there are no electric probs !