Intel Haswell low power states could require a new PSU


If you get your freak on by an extreme low power state you may need to get a new power supply if you want to use the new C6/C7 low power states of Intel's upcoming Haswell processors. These new power states require a power supply that can maintain a minimum current load of 0.05A on the CPU exclusive 12V2 rail.
The previous ATX12V v2.3 design guidelines called for a minimum load of 0.5A on the CPU power rail, so a lot of older and budget power supplies will likely not meet the new specification, resulting in stability or shutdown issues once the system enters the C6/C7 power state.
Unfortunately, there's no way to know which power supplies are fully Haswell compliant as PSU manufacturers do not usually report the minimum load on their specification sheets.
Older or bargain basement power supply units may be unable to achieve this, and might become unstable or trigger a UVP/OVP shutdown once the system enters the C6/C7 power states. This is because the previous ATX12V v2.3 design guidelines for Ivy Bridge and its predecessors only called for a minimum load of 0.5 Amps on the CPU power rail, hence a less sophisticated internal feedback loop/protection could be used in older or cost-reduced offerings, which will not support the new standards.
Most worryingly, PSU manufacturers (even the enthusiast grade ones) do not usually report the minimum load on their spec sheets, so it is virtually impossible for us to come up with a list of supported units at this time. To ensure a smooth transition, mainboard designers and system integrators have been told to implement a BIOS-level toggle to enable/disable the new C6/C7 power states.
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hmm, hopefully it wont be a issue
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They are introducing even lower power states in Haswell?well for laptops and tablets it will be a nice feature to prolong battery life but seriously their desktop cpu's should have an option on motherboard's bios to disable these new C6/C7 low power states if they are going to be an issue with your power supply,A lot of power users have invested in expensive top class PSU's it would be frustrating for who ever will be upgrading to the new platform and find out that they don't meet the those requirements.
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I'm for extremely low power usage, it needs to become more of a norm.
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I don't believe it. AMD FX processors can use C6 without requiring a new PSU....
Also vr-zone doesn't mention a source for this info; any article that begins with "According to our sources" should be taken with a grain of salt imho.....
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lol disable c6/7 state, overclock..and **** buying a new psu.
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The information given is too unspecific to be useful.
I doubt the new power states would be a requirement to use the chips, and the motherboard can handle the power states anyway.
The CPUs power is derived from 12V by the motherboards power circuits, there is no direct feed from the PSU.
Unless they are suggesting that the PSU might be damaged by having almost no load on it.
But those days are long gone, PSUs can be powered up with no load and not have any issue.
Maybe some cheap PSUs could have a problem, but I cant see mainstream mfrs falling foul.
edit:
to clarify, if the PSU has low current supply on its 12V, it wont cause a PSU shut down.
The shutdown signal is called PS_ON which wont be affected.
http://en.wikipedia.org/wiki/ATX
There is another signal called Power_OK or Power_Good
http://en.wikipedia.org/wiki/Power_Good_Signal
This shouldnt be triggered either in a decent PSU, because the PSU can easily maintain stable 12V with no load, so a tiny load shouldnt be a problem.
Don Altobello
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Noooooooo moooooorrrrreeeee POOOOOOWWWWWEEEEEEEEERRRRRRRRRR........
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If it can't hit 5 GHz off the hat I'm not interested.
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Doesn't every motherboard have the option to disable those? My last two have. Either way, for those of us overclocking it doesn't make a difference, we're disabling it anyway.
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If you get your freak on by an extreme low power state you may need to get a new power supply if you want to use the new C6/C7 low power states of Intel's upcoming Haswell processors. These new power...
Intel Haswell low power states could require a new PSU
for laptops sure, but for desktops cpus? hell no, I disable all that stuff cause IF i care about power usages I would get laptop, Washers ,dyers ,ac ,etc all use use way more power then any desktop pc and I find this constant power stat changing to be annoying and cause issues.
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This!

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Agreed 100%
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I dont believe it either. It borders on the ridiculous. Intel would not risk having thousands of failing machines and ruining their rep over something so stupid. Each Haswell would have to be sold with a disclaimer that your PSU may not be compatible and may need to upgrade for it to work. The high potential for a PR disaster is just too much, Intel would probably rather ditch Haswell rather than sell anything like this.
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That would mean I would have to downgrade. lol.
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Screw using low power designs! OVERCLOCK LIKE A BEAST!!!!