The 6-pin power connector is used to feed additional +5V and +3.3V rails to the motherboard.

Unless you get a super high end PSU, like a EVGA Supernova 1600 (and hope you have enough amps on the 5V rail), a modern PSU will not work. (your mb lacks a P4 connector)
Since the early 2000s, the focus has shifted towards the +12V rails (partly because of the Pentium 4 ), therefore modern PSUs have lots of current on the 12V rail, but not very much on the 5V rail.

Given that you actually have two CPUs, I would be concerned.

The SATA power connector is weak when we're talking power transfer. I would advise only using it for storage or other small power devices (fans, etc.)

Your Rosevill unit happens to be one of the cheap kind that has lots of amps on the 5V rail. It would be garbage for new PCs.

I'd say something like a period-correct Fortron Source Power (sold under various brands, AOpen is commonest in these parts of the woods) >300W PSU with big, heavy 5V line and aux connector. They weigh a ton, which is always a good indicator of quality. Of course you need to check for bad caps but they appear to have aged far better than say Antec PSUs. I have several FSP300-60BT(12V) that are ideal for this kind of build - 30A on the 5V line alone and nice proper AUX. I even have a 350W AOpen/FSP somewhere with 50W on 5V, but that's overkill for anything short of a dual AthlonMP.

Great thing about FSP is that despite their quality they aren't a much sought-after brand, so they can go pretty cheap even on auction sites. There's one of these units in the US going for USD 15 ONO at the moment.

computerguy08 wrote on 2020-05-24, 17:46:

The 6-pin power connector is used to feed additional +5V and +3.3V rails to the motherboard. […]
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The 6-pin power connector is used to feed additional +5V and +3.3V rails to the motherboard.

Unless you get a super high end PSU, like a EVGA Supernova 1600 (and hope you have enough amps on the 5V rail), a modern PSU will not work. (your mb lacks a P4 connector)
Since the early 2000s, the focus has shifted towards the +12V rails (partly because of the Pentium 4 ), therefore modern PSUs have lots of current on the 12V rail, but not very much on the 5V rail.

Given that you actually have two CPUs, I would be concerned.

The SATA power connector is weak when we're talking power transfer. I would advise only using it for storage or other small power devices (fans, etc.)

Your Rosevill unit happens to be one of the cheap kind that has lots of amps on the 5V rail. It would be garbage for new PCs.

Ah, that figures. I wasn't quite sure where my setup would be in terms of 3.3/5v reliance (only other P3 I've run on a newer PSU was a slot 1 500MHz+Voodoo 3 running on a CX430M). There is this guy on YouTube that has a pair of 1400's running on a seriously mediocre PSU, but his board is sorta odd in the sense that it's only got a 20-pin from the looks of it. I'd be curious as to how his setup has worked.

dionb wrote on 2020-05-24, 18:10:

I'd say something like a period-correct Fortron Source Power (sold under various brands, AOpen is commonest in these parts of the woods) >300W PSU with big, heavy 5V line and aux connector. They weigh a ton, which is always a good indicator of quality. Of course you need to check for bad caps but they appear to have aged far better than say Antec PSUs. I have several FSP300-60BT(12V) that are ideal for this kind of build - 30A on the 5V line alone and nice proper AUX. I even have a 350W AOpen/FSP somewhere with 50W on 5V, but that's overkill for anything short of a dual AthlonMP.

Great thing about FSP is that despite their quality they aren't a much sought-after brand, so they can go pretty cheap even on auction sites. There's one of these units in the US going for USD 15 ONO at the moment.

I'll certainly keep an eye peeled for them. If anything, I can rest easy knowing that I can completely ruin my current PSU extending the cables semi-properly (I've never touched a soldering iron in my life 🤣) and still have an easy escape route.

MII-233 wrote on 2020-05-24, 20:27:

dionb wrote on 2020-05-24, 18:10:

I'd say something like a period-correct Fortron Source Power (sold under various brands, AOpen is commonest in these parts of the woods) >300W PSU with big, heavy 5V line and aux connector. They weigh a ton, which is always a good indicator of quality. Of course you need to check for bad caps but they appear to have aged far better than say Antec PSUs. I have several FSP300-60BT(12V) that are ideal for this kind of build - 30A on the 5V line alone and nice proper AUX. I even have a 350W AOpen/FSP somewhere with 50W on 5V, but that's overkill for anything short of a dual AthlonMP.

Great thing about FSP is that despite their quality they aren't a much sought-after brand, so they can go pretty cheap even on auction sites. There's one of these units in the US going for USD 15 ONO at the moment.

I'll certainly keep an eye peeled for them. If anything, I can rest easy knowing that I can completely ruin my current PSU extending the cables semi-properly (I've never touched a soldering iron in my life 🤣) and still have an easy escape route.

Beware judging a PSU by weight as unscrupulous manufacturers have been known to ballast their supplies with lead or concrete. However, FSP is generally a good OEM who don't skimp on important design elements. Not as bulletproof as Delta, but still perfectly fine.

You should be able to use either an ATX 24 pin or 20 pin and P6 connector. The extra connectors both do the same job in reinforcing the 3.3V and 5V lines.

Speaking of Delta, you can often find very well built power supplies harvested from name brand computers of the era. Only look at ads that show the load table sticker so you can be sure what you're looking at pumps out enough power on the +5V lines. Delta, Lite-on, and Acbel are common and excellent (with Delta being arguably the best). Etasis and Zippy/Emacs are as good as Delta although more oriented towards server hardware. They're harder to find, but worth getting if you can find a model with the right load spec.

dionb wrote on 2020-05-24, 18:10:

I have several FSP300-60BT(12V) that are ideal for this kind of build - 30A on the 5V line alone and nice proper AUX. I even have a 350W AOpen/FSP somewhere with 50W on 5V, but that's overkill for anything short of a dual AthlonMP.
Great thing about FSP is that despite their quality they aren't a much sought-after brand, so they can go pretty cheap even on auction sites. There's one of these units in the US going for USD 15 ONO at the moment.

Yes a good price but too bad the shipping is so much, $22 anywhere in USA, $45 if shipped to Denmark from USA. Really ? should be $10 USA and $25 Denmark at the worst. Hate shipping gougers ! Would be better if seller said $25 for PSU and charged the actual shipping rates...
There is one if in Europe would be $36 Euro including shipping, look for ebay listing: "FSP Group FSP300-60BT Power Supply" and listing 133369820645

gdjacobs wrote on 2020-05-24, 23:06:

Delta, Lite-on, and Acbel are common and excellent (with Delta being arguably the best). Etasis and Zippy/Emacs are as good as Delta although more oriented towards server hardware. They're harder to find, but worth getting if you can find a model with the right load spec.

Agree ! Delta makes some bad-ass PSU, think most of the early Lite-On were oem Delta or Seasonic.

gdjacobs wrote on 2020-05-24, 23:06:

You should be able to use either an ATX 24 pin or 20 pin and P6 connector. The extra connectors both do the same job in reinforcing the 3.3V and 5V lines.

Oh really? I suppose that would explain builds I've seen with this board that have significantly more oompfh that only use the 24 pin. Guess I could have always looked at the pinout to figure that out, but where's the fun in that? 😜

Supermicro actually lists a 250W PSU (of the era) as a minimum for that board . https://www.supermicro.com/products/motherboa … /VIA/P3TDDE.cfm

Additionally, the manual recommends an ATX 2.02 or higher PSU , which is already 12V heavier than 1.x . I have no way of proving it, but I would not be surprised if this board is more 12V oriented than it's age would let on .

It would be interesting if someone tried it with the likes of a Corsair RM850i or other monitoring PSU to assess where the board really draws current from .

Horun wrote on 2020-05-25, 01:39:

[...]

Yes a good price but too bad the shipping is so much, $22 anywhere in USA, $45 if shipped to Denmark from USA. Really ? should be $10 USA and $25 Denmark at the worst. Hate shipping gougers ! Would be better if seller said $25 for PSU and charged the actual shipping rates...
There is one if in Europe would be $36 Euro including shipping, look for ebay listing: "FSP Group FSP300-60BT Power Supply" and listing 133369820645

I was assuming he was in USA, in EU there are other options, an early P4-era 350W PSU with 30A on 5V for similar price in Germany with assumedly much lower shipping costs to DK.

darry wrote on 2020-05-25, 02:44:

Supermicro actually lists a 250W PSU (of the era) as a minimum for that board . https://www.supermicro.com/products/motherboa … /VIA/P3TDDE.cfm

Specs like this should always be taken with a pinch of salt. A lot of PSUs out there fail to deliver their rated specification, or the rated spec is peak output, not sustained. So when indicating minimum PSU, most companies take a big, big margin of error. Considering that a P3 never draws over 40W, you're only talking 80W for the CPUs (which is 16A on 5V). AGP does max 2A from 5V line, with the bulk of heavy lifting in AGP Pro coming from 12V. Even assuming maximum loadout, you'd only need 250W if you had multiple heavy HDDs in there.

Additionally, the manual recommends an ATX 2.02 or higher PSU , which is already 12V heavier than 1.x . I have no way of proving it, but I would not be surprised if this board is more 12V oriented than it's age would let on .

It would be interesting if someone tried it with the likes of a Corsair RM850i or other monitoring PSU to assess where the board really draws current from .

Intriguing, but unlikely as it doesn't have an ATX12V connector. It does have the 24p ATX 2.x connector, so I suspect this is for the integration of aux power (extra 3.3V, 5V and 12V) into that rather than solely for 12V. But agreed that a measurement should put that to rest.

darry wrote on 2020-05-25, 02:44:

I have no way of proving it, but I would not be surprised if this board is more 12V oriented than it's age would let on .

Judging by the number of 5V lines present on the AUX and the 24-pin ATX connector, I can safely assume that it draws power from the 5V rails.

You can find the pinouts in the manual.

computerguy08 wrote on 2020-05-25, 08:04:

darry wrote on 2020-05-25, 02:44:

I have no way of proving it, but I would not be surprised if this board is more 12V oriented than it's age would let on .

Judging by the number of 5V lines present on the AUX and the 24-pin ATX connector, I can safely assume that it draws power from the 5V rails.

You can find the pinouts in the manual.

You mean connector J19 on page 2-7 , good point .
It really seems counter-productive that they would recommend an ATX 2.x PSU in this case .

darry wrote on 2020-05-25, 10:27:

You mean connector J19 on page 2-7 , good point .
It really seems counter-productive that they would recommend an ATX 2.x PSU in this case .

They could be technically correct, this document indicates that 12V rails became mandatory in ATX 2.1.

This doesn't seem to be obviously mentioned on the Wikipedia page.

computerguy08 wrote on 2020-05-25, 11:21:

darry wrote on 2020-05-25, 10:27:

You mean connector J19 on page 2-7 , good point .
It really seems counter-productive that they would recommend an ATX 2.x PSU in this case .

They could be technically correct, this document indicates that 12V rails became mandatory in ATX 2.1.

This doesn't seem to be obviously mentioned on the Wikipedia page.

The manual specifically mentions ATX 2.02 or above .

darry wrote on 2020-05-25, 14:47:

The manual specifically mentions ATX 2.02 or above .

Back then, they probably didn't know ATX 2.1 was going to be focused on 12V. So yeah, it is partially incorrect.