Radeon HD5770 on a 720W PSU

[Emoz93]

There's an article that states a Radeon HD5770 requires a 450 Watt power supply unit at minimum but that power supply needs to have (in total accumulated) at least 36 Amps available on the +12 volts rails. What does it mean?

I have a Gigabyte 720W PSU. According to the box, the max. output current for DC output of 12V1, 12V2 & 12V3 is 18A each. Is that it? Could it be that my PSU is not good enough for HD5770?

[Paradigm Shifter]

No, it's fine.

[Emoz93]

... that power supply needs to have (in total accumulated) at least 36 Amps available on the +12 volts rails. What does it mean?

Hold on, "in total accumulated"? Maybe it's like this: 18A + 18A +18A = 54A :doh

[Armenius]

The 5770 needs two PCI-E connectors, and each one is on its own +12V rail, meaning 36A combined and enough power for the card.

[Emoz93]

Two? :?:

Even Gigabyte's SOC edition of HD5770 has only a single 6-pin PCI Express power connector.

[candle86]

what 5770 has 2? I sell these things in my shop and have yet to see one with 2. As for PSU requirements they play on the safe side, ive personally sold two computers that are 100% stable equipped with a 380PSU, a 5770, 2gb DDR3, and AMD AThlon II X3 455's, and both where rock solid, but those PSU requirements take into account tring to say use an OC's AMD phenom 9950BE that will draw 150-160W OC'd

[stangflyer]

I am using a pc p@c 750 silencer with a 5970 oc to 875/1175 while gaming 5 internals hd/s, i7 920 at 4.1 and a case with 6 fans a and a xfi sound card. Runs all day long!

[Haldi]

once i put a Watt mesure behind my PSU :) Core 2 Duo E8400 @4ghz, 1.35V and HD6970 at 1.3V 980mhz.

If i'm Playing Crysis i need 350Watt! If i'm running Furmark and Prime95 together its 500Watt....

and i got an 550Watt PSU.

So you're 720W PSu should be fine even with an i7-980 OC'ed +5770.

[Slinky]

I ran two 5850's off of a single 700watt psu. you will be more than fine

[stone]

Some interesting texts about 12V rails:
So what's all this rubbish about multiple 12 volt rails?
A short history of PC power supply voltage rails