When will computers step up their secondary voltages?

[edro]

I have been noticing that some newer video cards require a power supply with a 30A 12v rail.

30 AMPS!
12v can only go so far.

It seems like the simple solution would be to some up with a new ATX style that is based on 24v.

UL/CSA requirements say secondary low voltage is <30v... so I don't think it would be a safety issue.

 

[Vette73]

Yea but just because something says 30 amps does not mean it will supply 30amps in real world usage.

 

[Demon-Xanth]

Personally, I'd like to see them go to a single 12V requirement and have boards do the conversion they need. Just have a beefy lug going to the MB.

Higher voltage=wider spacing needed to keep from arcing. 12V isn't much, but stepping up to 48V becomes a concern.

 

[SlickSnake]

When they become self aware and become one with Skynet.

 

[PottedMeat]

Originally posted by: Demon-Xanth
Personally, I'd like to see them go to a single 12V requirement and have boards do the conversion they need. Just have a beefy lug going to the MB.

Higher voltage=wider spacing needed to keep from arcing. 12V isn't much, but stepping up to 48V becomes a concern.

I wouldn't mind that - have 120VAC->12V High Current Removable Supply->Motherboard Step Down Converters.

 

[Demon-Xanth]

Originally posted by: PottedMeat

Originally posted by: Demon-Xanth
Personally, I'd like to see them go to a single 12V requirement and have boards do the conversion they need. Just have a beefy lug going to the MB.

Higher voltage=wider spacing needed to keep from arcing. 12V isn't much, but stepping up to 48V becomes a concern.

I wouldn't mind that - have 120VAC->12V High Current Removable Supply->Motherboard Step Down Converters.

It makes sense now. The CPU and videocard power supplies already do it. They only have 12V on their extra power connectors. Those are the two largest "high power draw" areas of a PC. An 800W power supply has 720W for the 12V vs. about 200W for everything else combined. (it's 800W for everything combined for those that do the math and complain)

 

[Howard]

Can you run that much current through a PCB?

 

[FoBoT]

the video card and cpu should have their own seperate power supplies

 

[trOver]

arching would become a problem really quick. Do you realize they put up to 8 layers of wires in pcb's these days? thats a lot of wires real close together

 

[Demon-Xanth]

Yup. There's a reason why there's wide traces

And lots and lots of pins. For example: LGA775 has 250 power and 273 ground pins. Think of all those pins like a stranded cable.

 

[Casawi]

Originally posted by: Howard
Can you run that much current through a PCB?

haha good point, but you design it to support that much current. The other thing is not all 30A goes down a single trace.

 

[Casawi]

Originally posted by: trOver
arching would become a problem really quick. Do you realize they put up to 8 layers of wires in pcb's these days? thats a lot of wires real close together

Actually PCBs are up to 16-layers in a very thin PCB, too. I was amazed. There is a lot of focus and engineering going into how to design High Frequency, High Current PCB. There is a book also called something like "Do it right the first time" about this.

 

[sciencewhiz]

Originally posted by: Howard
Can you run that much current through a PCB?

With a big enough trace. You're probably looking at a half an inch thick for 30 amps.

 

[piasabird]

A Power supply for a large video card would need some humongous Heat sinks and add a lot of weight to a motherboard.

It is getting to the point with power supplies that it might make sense to have 2 power supplies for a motherboard. Just wait till the 80 core processors come out. Not only will we have to have more power for such a processor, but the memory controller will probably need a lot more power along with the extra memory for the main memory and all the CPU registers.

 

[Kirby]

1.21 jiggawatts!

 

[Demon-Xanth]

Originally posted by: piasabird
A Power supply for a large video card would need some humongous Heat sinks and add a lot of weight to a motherboard.

It is getting to the point with power supplies that it might make sense to have 2 power supplies for a motherboard. Just wait till the 80 core processors come out. Not only will we have to have more power for such a processor, but the memory controller will probably need a lot more power along with the extra memory for the main memory and all the CPU registers.

http://i2.neoseeker.com/neo_im...r%20removed1_thumb.jpg
http://www.techpowerup.com/rev...ages/installation1.jpg
That right 3" or so on the video card is the videocard's power supply. It takes 12V in from the connector.