New PSU Spec from Intel

[CAD4466HK]

WTF?

[yanz]

Re: New PSU Spec from Intel

single voltage rail is a good idea

after googling for "smps vs linear psu" and read lots of pages i come to conclusion that it would be better if we only use single rail smps. (ok that's only my opinion).

[gonzo0815]

Re: New PSU Spec from Intel

Well, where i can buy the right model?
Oh yes, i know it is easy, but i have to build it for my self.
Isa there any easy step by step instruction?

[jonnyGURU]

Re: New PSU Spec from Intel

Not really.

I have these slides from the IDF.

This is in regards to Google bitching about their servers costing so much to power.

A single rail PSU would be more efficient in size and easier to cool because of this, and it is possible to make it more energy efficient, but while components are still requiring different voltages, additional DC to DC "point of power" converters will be needed.

So let's say you make a single 12V rail PSU and it's 85% to 90% efficient. You're still going to need to regulate voltage down to 3.3V for RAM, 5V for logic, etc. So we use mini point of power DC to DC power supplies. These can be 90% to 95% efficient. 90% of 90% is 81%. You're now LESS efficient than you were with a single multi-rail PSU.

I do agree with them on UPS's. Especially the Online UPS's that they use in the Google server farm and illustrate in one of the slides from the IDF. You're converting AC to DC to AC and then go to the PSU where you're converting back to DC. Why not just make the UPS AC to DC and then use a DC to DC power supply in the PC? Wouldn't that makes more sense????

[PeteS in CA]

Re: New PSU Spec from Intel

You could plug a SMPS set for 230VAC into 250-300VDC and run it.

[arneson]

Re: New PSU Spec from Intel

There are DC only server room designs being tested, but in the end you only save on air conditioning.

[yanz]

Re: New PSU Spec from Intel

So let's say you make a single 12V rail PSU and it's 85% to 90% efficient. You're still going to need to regulate voltage down to 3.3V for RAM, 5V for logic, etc. So we use mini point of power DC to DC power supplies. These can be 90% to 95% efficient. 90% of 90% is 81%. You're now LESS efficient than you were with a single multi-rail PSU.

That is the key, then. Lets's have some regulator/vrm for those two lower voltages on the motherboard, like the old days (when psu didn't have 3.3v yet).

How much is the efficiency on usual cpu vrm on motherboards? (12v -> ~1.5v)

[yanz]

Re: New PSU Spec from Intel

i mean, maybe it can make sense if the whole platform changed too.

[jonnyGURU]

Re: New PSU Spec from Intel

That is the key, then. Lets's have some regulator/vrm for those two lower voltages on the motherboard, like the old days (when psu didn't have 3.3v yet).

How much is the efficiency on usual cpu vrm on motherboards? (12v -> ~1.5v)

Still not 100%. Around 90 to 95%. That's going to add up and you're over all efficiency is only going to be 80 to 85%.

[gonzo0815]

Re: New PSU Spec from Intel

You can use independent 300v to 12&3v converters. I have seen a step down converter redy build for 6€. It is a 300v DC input to 5v /40A op. Tis was from an surpluss shop. I have thought to buy one and build it in my Amacrox Free Earth after the APFC section, so i can the PSu modding to only sinlge 12v rail and the 3,3v i can generate from the 12v line, as it wouldn`t used that mutch in todays equipment. This would be a cool mod