Haswell's C6/C7 low power states and PSU compatibility

[CA_Steve]

I came across this at VR Zone.

According to our sources, the new C6/C7 power states on the Haswell-Shark Bay platform will require the system power supply to be able to maintain a minimum current load of 0.05Amps on the CPU exclusive 12V2 rail

Don't know if it's fact or fiction

[Pappnaas]

AFAIK all states below C4 require Win8 (see: connected standby), Win7 has no support for the lower states. On other OS i do not know what is supported and what isn't.

But Win8? Meh... i'll probably skip on this one and wait for something more useful from Redmont.

[CA_Steve]

Windows 8 is also the only way to get to DirectX 11.1. Have to wait and see what Win 8.1 looks like. Rumors of Start button return and other Win7 UI features...

[rhuebner]

The PSU low power issue has been confirmed elsewhere, but will likely only be a problem with older and/or lower quality units. And it's expected that mobo makers will provide a BIOS setting to disable those ultra-low-power states for those whose gear won't handle them.

Just saw this statement from a Seasonic rep which I thought would be good to get logged here for SPCR's many Seasonic users:

Sorry we have not updated our website for this information.

The following series from Seasonic are Haswell compatible.
P, X, FL, G
M12II-650, 750, 850

I expect we'll be seeing similar statements from the other major makers over the next month or two.

[edh]

AFAIK all states below C4 require Win8 (see: connected standby), Win7 has no support for the lower states. On other OS i do not know what is supported and what isn't.

Most likely third party applications will become available to support these power states in older versions of Windows. This was the case for supporting C2 under Windows 98 many years ago with Athlon processors and later. Under Linux we already have cpupowerutils which should allow use of C7.

[CA_Steve]

Just saw this statement from a Seasonic rep which I thought would be good to get logged here for SPCR's many Seasonic users:

Thanks.

[subject42]

Am I correct in my reading that none of Seasonic's 80+ Platinum supplies support Haswell's C6/C7 power states? For some reason, I'm having a hard time reconciling their model identifiers with that forum post.

[faugusztin]

P = Platinum
X = Gold (X560-X860)
FL = Fanless (X400, X460)
G = G series (G360, G550 etc)
M12II-650, 750, 850 - no need to explain

[rhuebner]

Since there isn't really any Seasonic model series precisely named the "P series" in the same way as the X and G series, I'm just reading that as short for Platinum. Correlating that list with the Seasonic product list, it looks to me like the only products that aren't compatible are the M12II models less than 650W, and the S12II, M12D, and S12D series. Plus presumably any units older than those that are no longer listed in the product index.

[subject42]

So the SS-660XP should theoretically handle the new power states correctly? I'm starting to collect parts for a June build and I'd like to sort out the PSU sooner rather than later.

[CA_Steve]

Yes.

You know the release chipset has a bug than can prevent attached some USB devices (supposedly not mouse or keyboard) from mounting when the PC wakes from sleep, right? You have to unplug and replug the device to be recognized. Intel won't have the fixed chipset in mobo mfgrs hands until end July.

[subject42]

Yes.

You know the release chipset has a bug than can prevent attached some USB devices (supposedly not mouse or keyboard) from mounting when the PC wakes from sleep, right? You have to unplug and replug the device to be recognized. Intel won't have the fixed chipset in mobo mfgrs hands until end July.

I'm 100% aware of this. I figure that if the initial reviews paint it as a trainwreck I can wait. Honestly, though, I doubt it will be a big issue for me, since I tend to keep my PC running 24x7 and currently don't own any USB3 devices.


Side note. Corsair has started publishing compatibility for C6/C7 power states:

http://www.corsair.com/us/blog/haswell- ... -supplies/

[CA_Steve]

Yeah just saw the Corsair blog via Tech Report. The interesting bit is where Corsair says any PSU that derives the 3.3V and 5V rails from the 12V rail (via DC-DC conversion) won't have a problem.

[johannes]

Yeah just saw the Corsair blog via Tech Report. The interesting bit is where Corsair says any PSU that derives the 3.3V and 5V rails from the 12V rail (via DC-DC conversion) won't have a problem.

Does this mean PicoPSUs are fine? The blog post says that there's no problem because there's always some load on the 3.3V/5V rails, but I'm not sure how much load is enough - what uses these rails on a small, headless mini-itx system running from RAM?

[faugusztin]

Yes, pico PSU is again only a DC/DC system - you got an adapter which converts 110/230V to 12V and then the small PCB inside the computer only passes through 12V and converts part of it to 3.3V and 5V.

3.3V is mostly used by various motherboard components if needed, 5V mostly for hard drives. But there is a reason why those rails are so small .

[Abula]

Seasonic Power Supplies Ready for Intel's Haswell Processors

Sea Sonic Electronics congratulates Intel on the launch of the Haswell Processors. We are inspired by the continuing efforts made by Intel to push the boundaries of performance and at the same time, be environmentally conscious through reduction of energy consumption.

These are the exact same attributes which have driven Sea Sonic for the past 35+ years. As we strive for industry leading performance, we continue to research the long term effects of each of our design. By continuously improving our efficiency we try to achieve maximum energy savings and by using high quality components we aim to prolong product lifetime; all to achieve long term sustainability.

Our full lines of 80 PLUSR Platinum and Gold power supplies have been designed to be ready to meet Haswell's new technical requirements! The ultra efficient Platinum series, which also includes the industry leading true fanless models, and our long running, award winning X Series, which is now supported by the 80 PLUSRGold G series - are all Haswell READY! In addition, our 80 PLUSRBronze line up, consisting of the M12II-750 & 850W models, is also compatible to be used with Intel's new Haswell Processors.

[CA_Steve]

Be Quiet!'s PSU compatibility.

[CA_Steve]

Silverstone and Enermax compatibility via Hardware.info.

[CA_Steve]

There were a couple of missing PSUs in the Seasonic PR. So, I contacted Walter at Seasonic/EU (handle: Seasonic Rep). Here's his quick and detailed response:

Hi Steve,

Thank you very much for your support.

Please note the following.

ALL X, past, current & future models are Haswell Ready
This includes the X-560
ALL G, past, current & future models are Haswell Ready
ALL P, past, current & future models are Haswell Ready
ALL FL (Gold & Platinum), past, current & future models are Haswell Ready
ALL M12II AM series (M12II-650, 750, 850) past, current & future (Evo) models are Haswell Ready

M12II-520, 620 & S12II-520 & 620 ARE NOT Haswell Ready at this point in time.


Thank you,
Walter

So, looking good, unless you have a pretty old Bronze rated unit.

[Jordan]

I had no idea the brand name was actually 'Sea Sonic', I initially thought the PR person had made a huge blunder Is it just the the retail brand that's 'SeaSonic' then?

The link at the bottom of the article points to http://www.silentpcreview.com/www.seasonic.com

[andymcca]

ALL X, past, current & future models are Haswell Ready

TYVM for posting this.

I had no idea the brand name was actually 'Sea Sonic'

It looks like there is Seasonic USA and Sea Sonic Electronics (parent). http://www.seasonicusa.com/aboutus.htm
I also did not know this.
Edit: PS I see you are in the UK, and I didn't look at the other regional subsidiaries, but I imagine the naming schemes are similar?

[Garak]

It looks like there is Seasonic USA and Sea Sonic Electronics (parent).

Hit the nail on the head. Which is why I disagree with people writing SeaSonic rather than either Seasonic (without the second capital S) or Sea Sonic (with the space).

Edit: PS I see you are in the UK...

Makes no difference.

[zsl1010]

The 12 V2DC Minimum Current 0.05 A requirement is detailed in 3.2.10 of the

Power Supply
Design Guide for Desktop Platform Form Factors
Revision 1.31 April 2013

The recommended minimum current for +12 V2DC is however 0 A. That is in no load condition the +12 V2DC output should be within the 11.4 V to 12.6 V, ±5 % limits.

http://www.intel.com/cd/channel/reselle ... 215842.htm
http://cache-www.intel.com/cd/00/00/52/ ... 523796.pdf

[edh]

Kind of surprised this is not specified as a new version of the ATX standard. This would make things much easier to decipher moving forwards.

[silent_meerkat]

FSP just replied to me with a complete compatibility list.
I guess it's fresh news because I didn't see it posted elsewhere.

FSP PC powersuppliers will be the best choice to come with Intel “Haswell” platformwhich is 4th
‐Gen Core iseries.Haswell processoris an upgraded design that will offersignificant
powersavings and high performances.
FSP allseries of powersuppliers with various architectures are not only certify by 80PLUS on
Standard / Bronze / Sliver/Gold / Platinumefficiency level but also comply withHaswell
platformdemanding on performance feature. FSP powersuppliers canmeetthe
requirementsthatthe processor operatesmaximum18A at 12V2 peak to getthe best
performance on its platform.
The high‐end series powersuppliers of FSP within LLC&Active Clamp architecture are not
only certify by 80PLUS on Sliver/Gold / Platinumefficiency level but also comply with
Haswell platformdemanding on saving feature. The sleepingmode on C6/C7 will get
low‐powerstatesfromIvy Bridge 0.5ampstoHaswell 0.05amps and even strictto zero amp
onminimumload at 12V2.
We are the one to putzero amp with Active Clamp architecture successful within owned
ASIC named MIA ICTM in 2010 to follow the tendency.
Keep leading and converting with your choice onmid to high series of FSP!

Series Wattage Topology
HEXA 400W Double Forward
500W
600W Active‐Clamp
MIA ICTM
700W
RAIDER 450W
550W
650W
750W
AURUM 400W Active‐Clamp
MIA ICTM
500W
600W
700W
AURUM S 400W Active‐Clamp450W MIA ICTM
500W
550W
600W
650W
700W
750W
AURUM CM 550W Active‐Clamp
MIA ICTM
650W
750W
AURUM PRO 850W LLC
1000W Full Bridge
1200W
AURUM 92+ 450W Active‐Clamp
MIA ICTM
550W
650W
AURUM Xilenser 400W LLC
500W

[zsl1010]

FSP just replied to me with a complete compatibility list.
I guess it's fresh news because I didn't see it posted elsewhere.

It can be found in the fsp website.

http://www.fsplifestyle.com/news.php?LID=1&SN=111

The HEXA 400 W and 500 W are not C6/C7 compatible.

[CA_Steve]

Fractal Design PR:

The Newton R3 and Tesla R2 use the DC-DC method for generating the 3.3V and 5V rails. All power supplies
that use the DC-DC method are able to output their full 3.3V/5V ratings even with no load on the 12V
rail, so Tesla R2 and Newton R3 power supplies will easily support the new sleep states introduced with
Intel’s Haswell platform.

Newton R3
600W, 800W, 1000W Yes, compatible

Tesla R2
500W, 650W, 650W White, 800W, 1000W Yes, compatible

While Intel has not yet released their testing methodology or a formal definition of Haswell compatibility, we
have performed extensive tests with Integra R2 PSUs. The Integra R2 uses the group regulation method for
generating the 3.3V and 5V rails, which means output voltages will be affected by a large imbalance between
the load on those rails and the load on the 12V rail.

Current-generation group regulated power supplies are much more stable in this regard than power supply
platforms designed a few years ago, and the Integra R2 units will provide voltages within ATX specification
for any load levels on 3.3V and 5V likely to occur during system sleep.

Integra R2
500W, 650W, 750W Likely compatible

[CA_Steve]

be quiet! PR:

All current be quiet! power supply series, starting with the entry-level Pure Power L8 up to the high-end Dark Power Pro 10, are able to deliver smoothly the above mentioned low loads. The overview below shows which be quiet! PSU series are Haswell ready:

Dark Power Pro 10 (all models)
Straight Power E9 (all models)
Pure Power L8 (all models)
System Power 7 (all models)
Pure Power L7 (630W + 730W)

[zsl1010]

https://www.facebook.com/AntecInc?ref=s ... n=timeline

Antec C7-state PSU support overview

[Matthew9226]

I hope everyone now realizes that this is a non issue since Haswell is out now.
The S0ix isn't even enabled on these desktop SKU's.