20 pin ATX power into 24 pin motherboard?

[Jim Bancroft]

I have this case, which comes with a 20 pin ATX power cable. A number of motherboards I've looked at (most of the good ones, in fact) have 24 pin connectors on the board. Can I plug the 20 pin cord into these 24 pin ports, or do I need a converter of some sort?

 

[ts3433]

Don't tell me you're actually going to run a generic power supply with the kind of high-end board that would require a 24-pin in the first place....

I know there are adaptors, but you should really consider just getting a new PSU anyway. On the AMD side, the only ones I know of that have those connectors are some new NF4 boards, though.

 

[Dethfrumbelo]

You can, but the PCIE x 16 slot will be underpowered. Get a 20-to-24 pin adapter or a new ATX12V 2.0 PSU.

 

[batmanuel]

Originally posted by: Dethfrumbelo
You can, but the PCIE x 16 slot will be underpowered. Get a 20-to-24 pin adapter or a new ATX12V 2.0 PSU.

Depends on the board. My Intel 915 board says in the manual that you can run a 20-pin PSU plugged into the first 20 sockets on the power connector. If you are using a PCIe card that draws more than 75W, you can plug a Molex into the board near the x16 slot to give the slot the extra juice it needs.

 

[PascalT]

i ran my dfi nf4 with a 20 pinner, but it was a 550w antec, not a generic pos..

 

[John]

Yes, you can use a 20-pin ATX psu on the newer 24-pin motherboards. Do not use an adapter!

the ultimate "do i need a 24pin PSU ?" thread

 

[hotlips69]

Originally posted by: John
Yes, you can use a 20-pin ATX psu on the newer 24-pin motherboards. Do not use an adapter!

the ultimate "do i need a 24pin PSU ?" thread

I'm in a similar position to the original poster of this topic, apart from the fact that I have a high quality 400W PSU, albeit with a 20pin ATX connector.

What is the issue with a 20pin-24pin adapter?
The mobo that I am considering is an nforce4 Ultra, but I notice it has a molex connector on the board for some reason?

 

[hotlips69]

Anyone willing to answer???

 

[sharpnsmart]

Get the 20-24pin adapter.
It costs $5, and saves lots of potential hassle.
It's a no brainer really.
I've been using the adapter with my Enermax and A8N-SLI and it works perfectly, as it should.

 

[hotlips69]

Originally posted by: sharpnsmart
Get the 20-24pin adapter.
It costs $5, and saves lots of potential hassle.
It's a no brainer really.
I've been using the adapter with my Enermax and A8N-SLI and it works perfectly, as it should.

What does the adapter actually change when converting 20 to 24 pins, i.e. how can it add "extra 12v" if the PSU doesn't come with it as standard?

Also, I've been reading that these can make the overall PSU unstable...comments anyone?

 

[ChineseDemocracyGNR]

I wouldn't use an adaptor. If you have problems without one (which is not very likely) then it's time to get a different PSU.

 

[hotlips69]

Originally posted by: ChineseDemocracyGNR
I wouldn't use an adaptor. If you have problems without one (which is not very likely) then it's time to get a different PSU.

Please explain WHY?

 

[TheInvincibleMustard]

Extra resistance (more plugs = more resistance)
Harder strain on the cord coming out of the PSU (it's now supplying 2x12V pins instead of just one)
Adds another possible point of failure
Mobo thinks it has an ATX2.0 PSU when it actually doesn't (differen't specifications)
...

 

[John Keats]

For what it's worth, I'm using an Antec 350W power supply just fine w/the Gigabyte non-SLI Nforce4 board and 6600GT PCIexpress just fine with no adaptor and only 20 pins. I'd worry about the power supply more than the pins, myself, but I'm not a tech head. I mean, how good is a 400W Rosewill power supply? I dunno.

 

[TheInvincibleMustard]

Originally posted by: John Keats
I mean, how good is a 400W Rosewill power supply?

Not too good ... I'd rate them above Powmax, for sure, but below ThermalTake for sure as well. Mediocre entry-level PSUs, I'd say.

 

[Wadded Beef]

i have a vantec 420w 24 pin on my 20 pin nforce2 board. it uses a pointlessly long 24 to 20 pin adapter, but you won't need it. find a 420w+ vantec psu on ebay, they are 24 pin and very high quality

 

[ToeJam13]

It sounds like many new mainboards can detect if the extra 4 ATX pins are being powered, and if so, route that power directly to the PCIe bus. If not, it branches the main 12VDC line to all accessories, including the PCIe bus.

For the everyday Joe running a low- to mid-level video card and some 3rd party PCI/PCIe card, this will be more than enough current to handle your demand. High current draw CPUs may rely more on the AUX+4 CPU power feed, but you should be okay. Only the poorest rated power supplies will get you into trouble at this point.

The trouble begins when you start installing high power drawing cards such as enthusist video cards and multiprocessor crypto engines. It is compounded if your mainboard includes a large number of chips other than the northbridge, such as auxillary SATA, sound and network processors. These chips will all fight with the PCIe bus for that 12VDC rail on the 20-pin ATX cable. The result will be instability as voltage levels drop.

Older high wattage power supplies may be able to get around the issue if your video card has an auxillary power input that can be fed through your extra molex connectors. This is how things were done with the GeForce 6800 on the AGP bus, given AGP's much lower power delivery.

I think the real problem comes down to the power supply that comes with your case. Roseville isn't a horrible company, but who knows who they OEM this power supply from. If you plan on getting this case, do not expect to use the power supply with a GeForce 6800 or any SLI configuration. It should work fine for a GeForce 6200 and 6600/6600GT as long as you're not overclocking them or adding much else to the PCI bus.