Choosing a new ATX power supply for an expanded Amiga 4000 - Page 18

trixster · 28 May 2020, 20:42

There is a G4 one on eBay right now for £81

Or an 800mhz G3 for £348

Earlier this year you could buy the G4 one for several months for as low as £50

Liqourice · 29 May 2020, 00:58

Hmm. Have to look at that then. Need a mediator first though. But, I need to make my 4000 fully working to begin with, no sense buying new hardware until that's done.

Acill · 30 May 2020, 05:22

Quote:

Originally Posted by AC/DC HACKER!

After several other tests, and using my 68040 board I'm at the conclusion that the A4K PSU has something special about it that the Cyberstorm PPC uses when using the PPC. Amiga is having zero problems with SF450 and CS550M when playing AmigaAMP or anything that lightly uses the PPC or 68060 only. Some kind of change of energy is happening that I don't understand and it seems ATXs aren't able to handle, so the CyberstormPPC crashes when the demand isn't met.

Is ANYONE able to confirm this or...offer another solution? Is anyone able in the States or (cheap) enough to send one of these ATX's and convert it to AT? Or offer some other idea? I really don't want to pay a bit of cash to repair one of my A4K PSUs.

Do appreciate ALL the help that has been offered. I'm really scratching my head as to understand. I'm going to start looking around a bit more to see if I can find some other kind of Adapter solution. Maybe a power regulator someone has made? Any suggestions that DO function with CyberstormPPC?

All I did with his adapter is join more of the 5V lines and the ground lines together to supply more of the full 5V from his PSU. After talking with him for many hours over text I have decided to just buy him a new PSU and mail him one of my new Ian Steadman's designed big box adapter as well. I got him an SFX Silverstone thats well above what a 4000 would ever need. Reading more into this I see he has a fan on the CSPPC that draws 5V. I am starting to wonder if this fan is old and drawing more of the 5V than it should be and pulling down the voltage. I would highly recomend you pull that fan and replace it with another new one. Look for a good Pentium or 486 fan. if you can find a 12V and power it from a 12V line it would be even better.

If you want an AT PSU just order an AT? They are still available on Amazon new. Why you would want one is beyond me, and you would have to directly splice an A4K power connector to it. I guess you could attempt to find an AT to ATX adapter as well, but I havent ever seen anyone go that direction. Usual is to go from an ATX to an AT.

Acill · 30 May 2020, 05:34

Quote:

Originally Posted by AC/DC HACKER!

As I typed above, a few times, the 68060 of the CSPPC runs very well with the SF450 and CS550M, I've not noticed any crashes when using 68K. So A4000 with 68060, 68040 or below...are doing well.

For Cyberstorm MK3, I'm looking at http://www.ianstedman.co.uk/Amiga/de...x_adaptor.html as a solution. It LOOKS like Original/Big box adapter is the way to go. __LOOKS__ like. I'm still digging into information about it. Also talking to Paul (from earlier mention in this thread) about decoupling the PPC...but I don't yet understand what that means.

At: "Cost of recap:
A4000D PSU recap - skynet type - 80EUR - 87.23 USD
A4000D PSU recap - LiteOn type - 125EUR - 136.29 USD
Repair - depending what is broken - 20 to 150EUR - 21.81 to 163.55 USD
Postage back - 30EUR - 32.71 USD

Please send complete PSU with cover."

Is about 158.01 USD if it's simple. This is well over the price of a new or older ATX. Or if it's really broken 332.55 USD for my LiteOn. Which is highly expensive next to newer ATX PSU. I also understand the Amiga market is small and it's partly labor. Still, very high price as far as I'm concerned so I'm seeking alternatives. I'm not including the return trip.

I've asked you to ask the person that upgraded your CSPPC if he would tell you the values and locations of the decoupling caps used on the PPC on the bottom of the board. If they were not done I offered to do it for you and see if it helps. I know Stachu puts some pretty heavy caps on them.

Liqourice · 05 June 2020, 14:26

So, this is something I didn't realise until now that I'm trying to install my new SFX PSU.

What's that flat white connector on the Amigakit adapter for? It doesn't fit the floppy and there's nothing similar to it on the original PSU.

Also, where can I find an adapter cable that will fit into the floppy? Seems to be an expired product everywhere I check.

Liqourice · 05 June 2020, 14:35

Found out what the flat connector is for, I actually read the instructions that came with the adapter.

Still leaves me with finding a molex/sata to floppy adapter. Checked through all my old garbage but found none.

Liqourice · 05 June 2020, 14:52

One more thing.

The adapter doesn't match the 24-pin from the PSU. I know the adapter only has 20 pins and that 4 shouldn't be used but comparing them there will be pins that go to the motherboard connector that won't be fed if I put them together as they should be.

Edited to add:

Checked it more closely. That pin that won't be fed goes to the gray cable onto the whit flat connector on the adapter so it's not likely gonna be used. Still, really doesn't make sense to me.

Jope · 06 June 2020, 09:42

This is the -5 volt wire, which doesn't exist in 24pin ATX PSUs any more. It was phased out after PCs stopped having the ISA bus.

Thankfully the A4000 motherboard does not require this voltage.

The white flat connector is for an Elbox tower's busboard, which has ISA slots. Back when this tower was new, ATX power supplies with -5V were still readily available.

Liqourice · 06 June 2020, 13:37

Ah. Thanks for the explanation. To bad it wasn't a floppy connector instead. Hopefully a friend has a molex to floppy, they seem to be very hard to find these days.

Liqourice · 09 July 2020, 20:53

Well, my 4000 is now up and running with a Corsair SF450.

Though, the fan in the PSU is not spinning. I know why, there's not enough load on it. So, how can I change that in the best way?

AC/DC HACKER! · 09 July 2020, 22:03

The fan in the SF450 will spin after a bit. Mine spun when the PPC for my CyberstormPPC was being used. Not really *much* for the 68060. From Acill and Stan, and a lot of messaging back and forth I've learned that when Stan modifies a CyberstormPPC it's not *easy* to be able to be changed easily for SF450 and so on to function with it. So Acill is going to do repairs to my A4K PSU. I am not sending it over Seas..way too pricey for that.

Looks like you don't have a CyberstormPPC. In which case, the SF450 will great for you. I wish all of what I'm understanding now had been explained a lot better much earlier. Ah, well, not any regrets. Live and Learn.

Liqourice · 09 July 2020, 22:08

I'd rather it spun constantly, there are other things in there that could do with a bit of airflow.

I've been thinking about recapping my original PSU. Don't know if that's enough or if more needs to be done to it. I replaced the fan inside it 10+ years ago.

grelbfarlk · 10 July 2020, 04:12

Quote:

Originally Posted by Liqourice

I'd rather it spun constantly, there are other things in there that could do with a bit of airflow.

Tools:
Screwdriver
Tweezers
Fan to Drive adapter cable

With a minimum of effort you can open the SF450 power supply and unplug the fan from the PSU with tweezers and plug it into a 3-pin Fan to Drive cable. The connectors are not the same but with some jiggling it will fit.

You can either wire it for 12V or 5V, 12V will be fairly noisy and probably as loud as the original PSU fan but 5V will be quiet but might not give enough airflow.

Liqourice · 10 July 2020, 04:47

I've sent a question to Corsair. Not that I expect a good answer.

If I could find a SFX PSU that does this without modification I'd get that in a heartbeat, I can always use this PSU in a HTPC build instead.

DarrenHD · 10 July 2020, 05:24

Quote:

Originally Posted by spudje

AC/DC HACKER!you still might want to make 100% sure it's not a heat issue like in my case. If you have a big room fan on a stand, place it right next to your opened A4k case and blow air over the Zorro/PCI cards. If it still crashes you can be sure it's not heat. In my case it was. With fan, stable machine, taking fan away, crash within 10 to 15 minutes.

I have a "heat" issue with my older Elbox Mediator 4000Di. It's not a 3V version. If I run a fan beside it my system is stable. If I don't, it will usually get some sort of graphic corruption and eventually crash. My "newer" 3V Mediator 4000Di in my other A4000 doesn't have that issue.

grelbfarlk · 12 July 2020, 04:33

Quote:

Originally Posted by DarrenHD

I have a "heat" issue with my older Elbox Mediator 4000Di. It's not a 3V version. If I run a fan beside it my system is stable. If I don't, it will usually get some sort of graphic corruption and eventually crash. My "newer" 3V Mediator 4000Di in my other A4000 doesn't have that issue.

I wonder if there is any good reference for checking what brand and speed of chips are on everyone's Mediator bridges.

Quote:

Originally Posted by Liqourice

I've sent a question to Corsair. Not that I expect a good answer.

If I could find a SFX PSU that does this without modification I'd get that in a heartbeat, I can always use this PSU in a HTPC build instead.

I don't think what I suggested is close to being called a mod, you're unplugging a fan and plugging it into a drive connector.
There is the other option of putting an artificial load on the PSU so the fan spins higher but if you do it inside the case you're also creating extra heat which is the same thing you're trying to negate.

Liqourice · 12 July 2020, 13:55

The problem with this is that I have to make some mod to get the cable out of the PSU, make a hole somewhere or something.

05 June 2020, 14:52	#347
Liqourice Registered User Join Date: Jul 2018 Location: Stockholm / Sweden Posts: 107	One more thing. The adapter doesn't match the 24-pin from the PSU. I know the adapter only has 20 pins and that 4 shouldn't be used but comparing them there will be pins that go to the motherboard connector that won't be fed if I put them together as they should be. Edited to add: Checked it more closely. That pin that won't be fed goes to the gray cable onto the whit flat connector on the adapter so it's not likely gonna be used. Still, really doesn't make sense to me. Last edited by Liqourice; 05 June 2020 at 15:23.

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28 May 2020, 20:42	#341
trixster Guru Meditating Join Date: Jun 2014 Location: England Posts: 2,339	There is a G4 one on eBay right now for £81 Or an 800mhz G3 for £348 Earlier this year you could buy the G4 one for several months for as low as £50

29 May 2020, 00:58	#342
Liqourice Registered User Join Date: Jul 2018 Location: Stockholm / Sweden Posts: 107	Hmm. Have to look at that then. Need a mediator first though. But, I need to make my 4000 fully working to begin with, no sense buying new hardware until that's done.

05 June 2020, 14:26	#345
Liqourice Registered User Join Date: Jul 2018 Location: Stockholm / Sweden Posts: 107	So, this is something I didn't realise until now that I'm trying to install my new SFX PSU. What's that flat white connector on the Amigakit adapter for? It doesn't fit the floppy and there's nothing similar to it on the original PSU. Also, where can I find an adapter cable that will fit into the floppy? Seems to be an expired product everywhere I check.

05 June 2020, 14:35	#346
Liqourice Registered User Join Date: Jul 2018 Location: Stockholm / Sweden Posts: 107	Found out what the flat connector is for, I actually read the instructions that came with the adapter. Still leaves me with finding a molex/sata to floppy adapter. Checked through all my old garbage but found none.

06 June 2020, 09:42	#348
Jope - Join Date: Jul 2003 Location: Helsinki / Finland Age: 43 Posts: 9,862	This is the -5 volt wire, which doesn't exist in 24pin ATX PSUs any more. It was phased out after PCs stopped having the ISA bus. Thankfully the A4000 motherboard does not require this voltage. The white flat connector is for an Elbox tower's busboard, which has ISA slots. Back when this tower was new, ATX power supplies with -5V were still readily available.

06 June 2020, 13:37	#349
Liqourice Registered User Join Date: Jul 2018 Location: Stockholm / Sweden Posts: 107	Ah. Thanks for the explanation. To bad it wasn't a floppy connector instead. Hopefully a friend has a molex to floppy, they seem to be very hard to find these days.

09 July 2020, 20:53	#350
Liqourice Registered User Join Date: Jul 2018 Location: Stockholm / Sweden Posts: 107	Well, my 4000 is now up and running with a Corsair SF450. Though, the fan in the PSU is not spinning. I know why, there's not enough load on it. So, how can I change that in the best way?

09 July 2020, 22:03	#351
AC/DC HACKER! Registered User Join Date: Aug 2016 Location: Earth Posts: 884	The fan in the SF450 will spin after a bit. Mine spun when the PPC for my CyberstormPPC was being used. Not really much for the 68060. From Acill and Stan, and a lot of messaging back and forth I've learned that when Stan modifies a CyberstormPPC it's not easy to be able to be changed easily for SF450 and so on to function with it. So Acill is going to do repairs to my A4K PSU. I am not sending it over Seas..way too pricey for that. Looks like you don't have a CyberstormPPC. In which case, the SF450 will great for you. I wish all of what I'm understanding now had been explained a lot better much earlier. Ah, well, not any regrets. Live and Learn.

09 July 2020, 22:08	#352
Liqourice Registered User Join Date: Jul 2018 Location: Stockholm / Sweden Posts: 107	I'd rather it spun constantly, there are other things in there that could do with a bit of airflow. I've been thinking about recapping my original PSU. Don't know if that's enough or if more needs to be done to it. I replaced the fan inside it 10+ years ago.

10 July 2020, 04:47	#354
Liqourice Registered User Join Date: Jul 2018 Location: Stockholm / Sweden Posts: 107	I've sent a question to Corsair. Not that I expect a good answer. If I could find a SFX PSU that does this without modification I'd get that in a heartbeat, I can always use this PSU in a HTPC build instead.

12 July 2020, 13:55	#357
Liqourice Registered User Join Date: Jul 2018 Location: Stockholm / Sweden Posts: 107	The problem with this is that I have to make some mod to get the cable out of the PSU, make a hole somewhere or something.

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