While I have only a small amount of experience with Micro ATX power supplies as I generally put even Micro ATX motherboards into cases that can fit a regular sized ATX PSU, now that two others mentioned the brand so their Micro ATX PSUs are also seem to be built according to the same standard as their regular sized ones, I can also say that I never had an issue with a Corsair PSU, they are very dependable in my experience.

And as mentioned by NeoG_ a second hand PSU is also an option, the only thing with if you buy second hand is that always check the voltages of the PSU before connecting to the system with a multimeter and a dummy load (A dummy load is necessary because switching mode PSUs are either output not exactly the same voltages or won't start if there are no load, if you don't have a dummy load, you can use a not-working but still drawing power piece of HW like a faulty motherboard and a bad HDD to be the dummy load), and if the history of the PSU is not known then assume that the PSU went though heavy 24 hours per day usage and some components are aged so subtract 10% from the labelled wattage to be on the safe side.

PC Hoarder Patrol wrote on 2026-06-05, 01:25:

Never heard of them (least I know who CiT are). Top branded SFX models are readily available in the UK though, as previously me […]
Show full quote

DustyShinigami wrote on 2026-06-05, 00:32:

Are EVO Labs any good? I've come across a brand new EVO Labs Micro ATX PSU E-M400.

Never heard of them (least I know who CiT are). Top branded SFX models are readily available in the UK though, as previously mentioned, they do come with a higher price tag. Personally, all my small factor PSUs are either Corsair, SilverStone, be quiet! or FSP - other brands like Seasonic & Lian Li can be added to this mix...just don't expect to pick one up for £25.

Far as the heatsink goes, the Shuriken would be a decent choice - I have one on another ASRock skt 478 m-atx board. Just make sure it comes with the necessary skt 478 mounting clips. My pic makes it look like it overhangs the board but it doesn't really...only the very tips of the heatpipes do. Note that the larger Big Shuriken would definitely overhang.

The attachment Scythe Shuriken.JPG is no longer available

Great. Thanks. 😄 The Shuriken it is then.

FSP is the only brand I’ve come across so far, though the wattage and amperage has been fairly low for the ones I’ve seen. Even finding a more modern Micro ATX PSU is proving tricky.

NeoG_ wrote on 2026-06-05, 01:40:

See if you can find someone selling a second hand Corsair SF450 SFX power supply. I bought my SF600 at retail years ago and it's been nothing but perfect.

Thanks for the suggestion. I’ll take a look. 😀

MagefromAntares wrote on 2026-06-05, 04:45:

While I have only a small amount of experience with Micro ATX power supplies as I generally put even Micro ATX motherboards into cases that can fit a regular sized ATX PSU, now that two others mentioned the brand so their Micro ATX PSUs are also seem to be built according to the same standard as their regular sized ones, I can also say that I never had an issue with a Corsair PSU, they are very dependable in my experience.

And as mentioned by NeoG_ a second hand PSU is also an option, the only thing with if you buy second hand is that always check the voltages of the PSU before connecting to the system with a multimeter and a dummy load (A dummy load is necessary because switching mode PSUs are either output not exactly the same voltages or won't start if there are no load, if you don't have a dummy load, you can use a not-working but still drawing power piece of HW like a faulty motherboard and a bad HDD to be the dummy load), and if the history of the PSU is not known then assume that the PSU went though heavy 24 hours per day usage and some components are aged so subtract 10% from the labelled wattage to be on the safe side.

Hmm, okay. The only faulty hardware I have would be that Deathstar HDD. I have no motherboards though.

DustyShinigami wrote on 2026-06-05, 09:21:

MagefromAntares wrote on 2026-06-05, 04:45:

While I have only a small amount of experience with Micro ATX power supplies as I generally put even Micro ATX motherboards into cases that can fit a regular sized ATX PSU, now that two others mentioned the brand so their Micro ATX PSUs are also seem to be built according to the same standard as their regular sized ones, I can also say that I never had an issue with a Corsair PSU, they are very dependable in my experience.

And as mentioned by NeoG_ a second hand PSU is also an option, the only thing with if you buy second hand is that always check the voltages of the PSU before connecting to the system with a multimeter and a dummy load (A dummy load is necessary because switching mode PSUs are either output not exactly the same voltages or won't start if there are no load, if you don't have a dummy load, you can use a not-working but still drawing power piece of HW like a faulty motherboard and a bad HDD to be the dummy load), and if the history of the PSU is not known then assume that the PSU went though heavy 24 hours per day usage and some components are aged so subtract 10% from the labelled wattage to be on the safe side.

Hmm, okay. The only faulty hardware I have would be that Deathstar HDD. I have no motherboards though.

With a HDD only the load would be most likely <10W when idling, most likely enough for the PSU to start outputting power, but having stable voltages at less than 5% of capacity of the PSU doesn't mean that the voltages will be stable at a proper load, still better than testing with absolutely no load however, as most fatal issues like "Outputting line voltage on one of the output pins" or having "5 volts completely missing" will be most likely shown even with testing with a small load like this. However if you don't have a motherboard, then you will have to connect the power pin(Pin 16, if color coded green) to one of the grounds(The Pin 15, if color coded black, next to it should be good) on the connector to have an ATX PSU to start.

If the negative voltages are not too stable, or if -5 Volts is missing then you can most likely can ignore it, negative voltages are not used by P4 era HW, and -5 volts are intentionally missing from later PSUs as it was removed IIRC in V1.3 of the ATX standard.

MagefromAntares wrote on 2026-06-05, 09:35:

DustyShinigami wrote on 2026-06-05, 09:21:

MagefromAntares wrote on 2026-06-05, 04:45:

While I have only a small amount of experience with Micro ATX power supplies as I generally put even Micro ATX motherboards into cases that can fit a regular sized ATX PSU, now that two others mentioned the brand so their Micro ATX PSUs are also seem to be built according to the same standard as their regular sized ones, I can also say that I never had an issue with a Corsair PSU, they are very dependable in my experience.

And as mentioned by NeoG_ a second hand PSU is also an option, the only thing with if you buy second hand is that always check the voltages of the PSU before connecting to the system with a multimeter and a dummy load (A dummy load is necessary because switching mode PSUs are either output not exactly the same voltages or won't start if there are no load, if you don't have a dummy load, you can use a not-working but still drawing power piece of HW like a faulty motherboard and a bad HDD to be the dummy load), and if the history of the PSU is not known then assume that the PSU went though heavy 24 hours per day usage and some components are aged so subtract 10% from the labelled wattage to be on the safe side.

Hmm, okay. The only faulty hardware I have would be that Deathstar HDD. I have no motherboards though.

With a HDD only the load would be most likely <10W when idling, most likely enough for the PSU to start outputting power, but having stable voltages at less than 5% of capacity of the PSU doesn't mean that the voltages will be stable at a proper load, still better than testing with absolutely no load however, as most fatal issues like "Outputting line voltage on one of the output pins" or having "5 volts completely missing" will be most likely shown even with testing with a small load like this. However if you don't have a motherboard, then you will have to connect the power pin(Pin 16, if color coded green) to one of the grounds(The Pin 15, if color coded black, next to it should be good) on the connector to have an ATX PSU to start.

If the negative voltages are not too stable, or if -5 Volts is missing then you can most likely can ignore it, negative voltages are not used by P4 era HW, and -5 volts are intentionally missing from later PSUs as it was removed IIRC in V1.3 of the ATX standard.

Okay. I mean, I do have my MSI MS-6156 BX11 board I could test with. It’s not faulty, and I’d prefer not to damage it, but it wouldn’t be a massive loss if anything were to happen to it.

Also, I’m getting a bit confused now with the various form factor names. Some names seem to be interchangeable or are getting mixed up. I’ve been calling Micro ATX ‘mini ATX’ when I believe it’s actually ‘Mini ITX’…? And instead of it being referred to as ‘Micro ATX PSU’ it should be ‘SFX PSU’…? Or is ‘Micro ATX PSU’ valid?

DustyShinigami wrote on 2026-06-05, 09:49:

Also, I’m getting a bit confused now with the various form factor names. Some names seem to be interchangeable or are getting mixed up. I’ve been calling Micro ATX ‘mini ATX’ when I believe it’s actually ‘Mini ITX’…? And instead of it being referred to as ‘Micro ATX PSU’ it should be ‘SFX PSU’…? Or is ‘Micro ATX PSU’ valid?

I know it is Wikipedia, but seems to be mostly correct:https://en.wikipedia.org/wiki/Motherboard_form_factor

And yes there are quite many, but the most important ones for desktops are AT, Baby-AT, microATX, Mini-ATX, Mini-ITX(Maybe LPX can be on this list too, as it is used by OEMs relatively often, but unlikely if you assemble the PC yourself). The other ones are either not for desktops or very rare.

EDIT: Whoops, I have missed ATX itself from the important list 😁

MagefromAntares wrote on 2026-06-05, 09:55:

I know it is Wikipedia, but seems to be mostly correct:https://en.wikipedia.org/wiki/Motherboard_form_factor […]
Show full quote

DustyShinigami wrote on 2026-06-05, 09:49:

Also, I’m getting a bit confused now with the various form factor names. Some names seem to be interchangeable or are getting mixed up. I’ve been calling Micro ATX ‘mini ATX’ when I believe it’s actually ‘Mini ITX’…? And instead of it being referred to as ‘Micro ATX PSU’ it should be ‘SFX PSU’…? Or is ‘Micro ATX PSU’ valid?

I know it is Wikipedia, but seems to be mostly correct:https://en.wikipedia.org/wiki/Motherboard_form_factor

And yes there are quite many, but the most important ones for desktops are AT, Baby-AT, microATX, Mini-ATX, Mini-ITX(Maybe LPX can be on this list too, as it is used by OEMs relatively often, but unlikely if you assemble the PC yourself). The other ones are either not for desktops or very rare.

EDIT: Whoops, I have missed ATX itself from the important list 😁

Thanks. I don’t see much mentioned about PSU standards. Do SFX PSUs fit into Micros…? I’m guessing the dimensions are completely different?

DustyShinigami wrote on 2026-06-05, 10:05:

MagefromAntares wrote on 2026-06-05, 09:55:

I know it is Wikipedia, but seems to be mostly correct:https://en.wikipedia.org/wiki/Motherboard_form_factor […]
Show full quote

DustyShinigami wrote on 2026-06-05, 09:49:

Also, I’m getting a bit confused now with the various form factor names. Some names seem to be interchangeable or are getting mixed up. I’ve been calling Micro ATX ‘mini ATX’ when I believe it’s actually ‘Mini ITX’…? And instead of it being referred to as ‘Micro ATX PSU’ it should be ‘SFX PSU’…? Or is ‘Micro ATX PSU’ valid?

I know it is Wikipedia, but seems to be mostly correct:https://en.wikipedia.org/wiki/Motherboard_form_factor

And yes there are quite many, but the most important ones for desktops are AT, Baby-AT, microATX, Mini-ATX, Mini-ITX(Maybe LPX can be on this list too, as it is used by OEMs relatively often, but unlikely if you assemble the PC yourself). The other ones are either not for desktops or very rare.

EDIT: Whoops, I have missed ATX itself from the important list 😁

Thanks. I don’t see much mentioned about PSU standards. Do SFX PSUs fit into Micros…? I’m guessing the dimensions are completely different?

The SFX is smaller than the MicroATX so physically it will fit, I don't remember if the mounting holes for the screws are in compatible positions however. (If you are really into DIY then you can fix it with a good drill and a proper drill bit 😁).

EDIT: Before anyone accidentally taking my DIY advice serious, even if you do, drill the holes into the case, not into the PSU, drilling holes into the PSU is dangerous!

DustyShinigami wrote on 2026-06-05, 10:05:

MagefromAntares wrote on 2026-06-05, 09:55:

I know it is Wikipedia, but seems to be mostly correct:https://en.wikipedia.org/wiki/Motherboard_form_factor […]
Show full quote

DustyShinigami wrote on 2026-06-05, 09:49:

Also, I’m getting a bit confused now with the various form factor names. Some names seem to be interchangeable or are getting mixed up. I’ve been calling Micro ATX ‘mini ATX’ when I believe it’s actually ‘Mini ITX’…? And instead of it being referred to as ‘Micro ATX PSU’ it should be ‘SFX PSU’…? Or is ‘Micro ATX PSU’ valid?

I know it is Wikipedia, but seems to be mostly correct:https://en.wikipedia.org/wiki/Motherboard_form_factor

And yes there are quite many, but the most important ones for desktops are AT, Baby-AT, microATX, Mini-ATX, Mini-ITX(Maybe LPX can be on this list too, as it is used by OEMs relatively often, but unlikely if you assemble the PC yourself). The other ones are either not for desktops or very rare.

EDIT: Whoops, I have missed ATX itself from the important list 😁

Thanks. I don’t see much mentioned about PSU standards. Do SFX PSUs fit into Micros…? I’m guessing the dimensions are completely different?

This is probaby a more comprehensive Wiki page... https://en.wikipedia.org/wiki/ATX

Generally SFF is for cases, SFX & TFX is for power supplies and micro (m) / mini (m)-atx / itx is for motherboards, though there are plenty examples of both natural and poorly applied terminology overlaps.

Post some pics of both your current psu and the rear of the case where the psu fits (why I asked in the earlier PM)

PC Hoarder Patrol wrote on 2026-06-05, 10:17:

This is probaby a more comprehensive Wiki page... https://en.wikipedia.org/wiki/ATX […]
Show full quote

DustyShinigami wrote on 2026-06-05, 10:05:

MagefromAntares wrote on 2026-06-05, 09:55:

I know it is Wikipedia, but seems to be mostly correct:https://en.wikipedia.org/wiki/Motherboard_form_factor

And yes there are quite many, but the most important ones for desktops are AT, Baby-AT, microATX, Mini-ATX, Mini-ITX(Maybe LPX can be on this list too, as it is used by OEMs relatively often, but unlikely if you assemble the PC yourself). The other ones are either not for desktops or very rare.

EDIT: Whoops, I have missed ATX itself from the important list 😁

Thanks. I don’t see much mentioned about PSU standards. Do SFX PSUs fit into Micros…? I’m guessing the dimensions are completely different?

This is probaby a more comprehensive Wiki page... https://en.wikipedia.org/wiki/ATX

Generally SFF is for cases, SFX & TFX is for power supplies and micro (m) / mini (m)-atx / itx is for motherboards, though there are plenty examples of both natural and poorly applied terminology overlaps.

Post some pics of both your current psu and the rear of the case where the psu fits (why I asked in the earlier PM)

Okay, thanks. Argh. So you did. 😖 Sorry. I’ll get some pics taken a bit later.

But no, I’ll avoid getting an SFX then. I certainly don’t want to manually adjust anything to make them fit

PC Hoarder Patrol wrote on 2026-06-05, 10:17:

This is probaby a more comprehensive Wiki page... https://en.wikipedia.org/wiki/ATX […]
Show full quote

DustyShinigami wrote on 2026-06-05, 10:05:

MagefromAntares wrote on 2026-06-05, 09:55:

I know it is Wikipedia, but seems to be mostly correct:https://en.wikipedia.org/wiki/Motherboard_form_factor

And yes there are quite many, but the most important ones for desktops are AT, Baby-AT, microATX, Mini-ATX, Mini-ITX(Maybe LPX can be on this list too, as it is used by OEMs relatively often, but unlikely if you assemble the PC yourself). The other ones are either not for desktops or very rare.

EDIT: Whoops, I have missed ATX itself from the important list 😁

Thanks. I don’t see much mentioned about PSU standards. Do SFX PSUs fit into Micros…? I’m guessing the dimensions are completely different?

This is probaby a more comprehensive Wiki page... https://en.wikipedia.org/wiki/ATX

Generally SFF is for cases, SFX & TFX is for power supplies and micro (m) / mini (m)-atx / itx is for motherboards, though there are plenty examples of both natural and poorly applied terminology overlaps.

Post some pics of both your current psu and the rear of the case where the psu fits (why I asked in the earlier PM)

Okay, here's some pics. This was the case/system I first bought off eBay a few years ago, which is a Tiny model.

One more:

PC Hoarder Patrol wrote on 2026-06-05, 01:25:

Never heard of them (least I know who CiT are). Top branded SFX models are readily available in the UK though, as previously me […]
Show full quote

DustyShinigami wrote on 2026-06-05, 00:32:

Are EVO Labs any good? I've come across a brand new EVO Labs Micro ATX PSU E-M400.

Never heard of them (least I know who CiT are). Top branded SFX models are readily available in the UK though, as previously mentioned, they do come with a higher price tag. Personally, all my small factor PSUs are either Corsair, SilverStone, be quiet! or FSP - other brands like Seasonic & Lian Li can be added to this mix...just don't expect to pick one up for £25.

Far as the heatsink goes, the Shuriken would be a decent choice - I have one on another ASRock skt 478 m-atx board. Just make sure it comes with the necessary skt 478 mounting clips. My pic makes it look like it overhangs the board but it doesn't really...only the very tips of the heatpipes do. Note that the larger Big Shuriken would definitely overhang.

The attachment Scythe Shuriken.JPG is no longer available

Hmm. The one I'm looking at doesn't appear to have the brackets. I've dropped the seller a message, so just waiting to hear back. Other models look to be sold from Germany, so the shipping price would double the overall price.

Hmmm, seems like a power supply form factor that you basically can't find today.. Doesn't match ATX, SFX/L, TFX or FlexATX. SFX would certainly fit in the space but it would need a custom adapter plate.

NeoG_ wrote on 2026-06-05, 12:01:

Hmmm, seems like a power supply form factor that you basically can't find today.. Doesn't match ATX, SFX/L, TFX or FlexATX. SFX would certainly fit in the space but it would need a custom adapter plate.

Yeah. For some reason I thought it said on the label what type it is, but it doesn't. And neither does a Google search. It's looking more likely that I'll need to get mid-tower case. I do have a spare ATX PSU that might be okay...?

DustyShinigami wrote on 2026-06-05, 12:10:

NeoG_ wrote on 2026-06-05, 12:01:

Hmmm, seems like a power supply form factor that you basically can't find today.. Doesn't match ATX, SFX/L, TFX or FlexATX. SFX would certainly fit in the space but it would need a custom adapter plate.

Yeah. For some reason I thought it said on the label what type it is, but it doesn't. And neither does a Google search. It's looking more likely that I'll need to get mid-tower case. I do have a spare ATX PSU that might be okay...?

The attachment IMG_5550.JPG is no longer available

FSP is a brand that I recognize, I have seen a few of these here in Hungary, they are not at the top-tier level of Corsair, but I don't remember having too much problem with them either.

DustyShinigami wrote on 2026-06-05, 12:10:

NeoG_ wrote on 2026-06-05, 12:01:

Hmmm, seems like a power supply form factor that you basically can't find today.. Doesn't match ATX, SFX/L, TFX or FlexATX. SFX would certainly fit in the space but it would need a custom adapter plate.

Yeah. For some reason I thought it said on the label what type it is, but it doesn't. And neither does a Google search. It's looking more likely that I'll need to get mid-tower case. I do have a spare ATX PSU that might be okay...?

The attachment IMG_5550.JPG is no longer available

Kinda looks SFX to me...check the centre hole spacings to see (as measured against one of my SilverStone models)

PC Hoarder Patrol wrote on 2026-06-05, 12:23:

Kinda looks SFX to me...check the centre hole spacings to see (as measured against one of my SilverStone models)

According to the manufacturers website this is definitely larger than SFX:https://www.fsp-group.com/en/product/pcpsu/14 … 235198-107.html

MagefromAntares wrote on 2026-06-05, 12:26:

PC Hoarder Patrol wrote on 2026-06-05, 12:23:

Kinda looks SFX to me...check the centre hole spacings to see (as measured against one of my SilverStone models)

According to the manufacturers website this is definitely larger than SFX:https://www.fsp-group.com/en/product/pcpsu/14 … 235198-107.html

I'm referring to the Hipro (as pictured) rather than the FSP