power suply requirements

zemecksis

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Jul 29, 2014
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I'm going to build a new computer with this spec
i5 4690k
gigabyte ga z97x gaming 3
ati amd r9 280x
sandisk extreme 240gb ssd
wd caviar black 1tb

how much wattage of minimum psu requirements
can I still use my old corsair cx500 while waiting the new one?

 

zemecksis

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Jul 29, 2014
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thank you
yes its run well with my old corsair cx500, I'm just finishing my new rig
after asking and searching I figure it out that 500 watt is meet the minimum wattage requirement for my build as long as not to oc and use only 1 gpu and use trusted psu brand
since I dont intend to oc my new rig I guess my old cx500 good enough while I safe money to buy 550-650 watt psu

 

Dark Lord of Tech

Retired Moderator
CX500 isn't Haswell compatible. :(

When an Intel Core (i3, i5, i7) processor is idle, it goes into a sleep state that requires less power than when the CPU is active. Since the motherboard voltage regulation modules that provide power to the CPU gets their power from the power supply's +12V rail, these sleep states can dramatically reduce the load on the power supply's +12V rail.

According to Intel's presentation at IDF, the new Haswell processors enter a sleep state called C7 that can drop processor power usage as low as 0.05A. Even if the sleeping CPU is the only load on the +12V rail, most power supplies can handle a load this low. The potential problem comes up when there is still a substantial load on the power supply's non-primary rails (the +3.3V and +5V). If the load on these non-primary rails are above a certain threshold (which varies by PSU), the +12V can go out of spec (voltages greater than +12.6V). If the +12V is out of spec when the motherboard comes out of the sleep state, the PSU's protection may prevent the PSU from running and will cause the power supply to "latch off". This will require the user to cycle the power on their power supply using the power switch on the back of the unit.

While we are still working with Intel on the details of the testing methodology they use to check PSUs for Haswell compatibility, it is already known that a power supply that uses DC to DC for the non-primary rails (the +3.3V and +5V) will not have an issue with the new low power sleep states. This is because a DC to DC buck converter is used to convert +12V to +3.3V and +5V. This means that no matter what load the CPU puts on the power supply, there will always be a load on the +12V because the +12V is required to provide power to +3.3V and +5V.

Corsair utilizes this DC to DC technology in most of their power supplies. Starting with the CX750 and CX750M and moving all of the way through the GS Series, TX and TX-M Series, the HX Series, both the AX Series Gold and AX Series Platinum, and the new AXi Series. So whatever your budget, if you choose Intel's new Haswell processor and wish to utilize the new, low power C7 sleep state, Corsair has a power supply for you.


corsair.com
 

zemecksis

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Jul 29, 2014
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thank you
well I think I cant use my new rig for a while now, just wait for my new PSU
probably CX750 or CX750M my new list to buy