English Amiga Board - View Single Post - A4000

MarkT · 19 June 2022, 22:59

I've come up with a suitable PSU solution...and I'm relieved to say it works! It's a hybrid of those documented by RMC ( [ Show youtube player ]) and the The Future Was 8 Bit (https://www.thefuturewas8bit.com/a4000psu-upgrade). My objective was to minimise electrical modifications after scaring myself last time around, plus eliminate metalwork modifications. Essentially, I wanted the new supply to be invisible from the outside and fully reversible with a little work.

I've gone with a bequiet! 300W SFX PSU, and checked on their website to confirm that it does indeed have a separate 5V DC-to-DC Converter so should offer excellent voltage stability. The standard 80mm fan it has was an easy direct replacement for the existing one. To take the supply to the motherboard I purchased an A4000 ATX PSU adapter from AmigaKit.

To avoid any metalwork modifications, I made a small adapter plate using a polycarbonate sheet and some hardware I had lying around. The sheet I had was too thick to fit into the notch at the rear of the PSU box so I glued on a foot instead. The SFX PSU sits on top of it after being removed from its original case. The mains cabling has been lightly modified to remove the switch from the mains circuit - the A4000 power button now operates the ATX low voltage on/off signal instead.

I've not taken all of the LV cables out of the PSU case, as they won't all fit. However, there's more than enough connectors to power everything that fit inside the A4000's compact dimensions. I'm hoping to figure out how to upload some pics so it makes more sense!

One downside of my solution is there's lots of 'excess' cabling left in the case, and therefore I think it'll be difficult to fit the second 'Power XL' floppy drive I have back in. I may just go for a Gotek in the same bay instead as I predict it'll be much more useful.

Now I'm onto setting up my CF card. The 32GB SanDisk Extreme I have works fine in WinUAE and boots into a clean OS3.2 install. Annoyingly the real hardware doesn't boot at all and just sits waiting for a floppy disk! However, it'll have to wait as I've expended a lot of time on this project already. I'll see how I get on over the next couple of weeks.

19 June 2022, 22:59	#31
MarkT Registered User Join Date: May 2021 Location: North Wales Posts: 42	I've come up with a suitable PSU solution...and I'm relieved to say it works! It's a hybrid of those documented by RMC ( [ Show youtube player ]) and the The Future Was 8 Bit (https://www.thefuturewas8bit.com/a4000psu-upgrade). My objective was to minimise electrical modifications after scaring myself last time around, plus eliminate metalwork modifications. Essentially, I wanted the new supply to be invisible from the outside and fully reversible with a little work. I've gone with a bequiet! 300W SFX PSU, and checked on their website to confirm that it does indeed have a separate 5V DC-to-DC Converter so should offer excellent voltage stability. The standard 80mm fan it has was an easy direct replacement for the existing one. To take the supply to the motherboard I purchased an A4000 ATX PSU adapter from AmigaKit. To avoid any metalwork modifications, I made a small adapter plate using a polycarbonate sheet and some hardware I had lying around. The sheet I had was too thick to fit into the notch at the rear of the PSU box so I glued on a foot instead. The SFX PSU sits on top of it after being removed from its original case. The mains cabling has been lightly modified to remove the switch from the mains circuit - the A4000 power button now operates the ATX low voltage on/off signal instead. I've not taken all of the LV cables out of the PSU case, as they won't all fit. However, there's more than enough connectors to power everything that fit inside the A4000's compact dimensions. I'm hoping to figure out how to upload some pics so it makes more sense! One downside of my solution is there's lots of 'excess' cabling left in the case, and therefore I think it'll be difficult to fit the second 'Power XL' floppy drive I have back in. I may just go for a Gotek in the same bay instead as I predict it'll be much more useful. Now I'm onto setting up my CF card. The 32GB SanDisk Extreme I have works fine in WinUAE and boots into a clean OS3.2 install. Annoyingly the real hardware doesn't boot at all and just sits waiting for a floppy disk! However, it'll have to wait as I've expended a lot of time on this project already. I'll see how I get on over the next couple of weeks.