What power supply for Radeon R9 280X?

[barry86]

I am planning to have my gaming PC built by PC Specialist and have recently been doing some window shopping, configuring some possible specs etc. and have one question concerning choosing the right power supply unit for my graphics card.

Namely, I already own a brand new Asus Radeon R9 280X DirectCU II Top edition and on its original packaging it says that the recommended system requirements for the card include a "minimum 750W system power supply (with a minimum 12V current rating of 24A)".

However, when configuring a hypothetical Intel-based system and including that very model of graphics card, their website tells me that a Corsair 550W power supply is enough to run the system: "You have selected a 650W power supply, but based on our calculations you actually only need a 550W power supply. We have calculated your specification to require around 486W of power including a 20% allowance."

Now, if I get things right - 20% allowance for a 486W use is an extra 97W which is 583W in total. A little more than a 550W PSU can give. When investing so much money in a desktop, I need to be 100% sure that I'm choosing only the right components, especially the PSU, since it was the PSU in my previous desktop that cooked both the motherboard and everything on it and turned a brilliant-working computer into a piece of junk within just a split second.

So here comes the question - what power supply does Asus Radeon R9 280X require and, most importantly, why?

 

[Dark Lord of Tech]

A Radeon R9-280X needs 30 amps on the 12v + rail and a 550 watt power supply with 1 - 6 pin and 1 - 8 pin PCIE connections.

A 650w power supply would be the perfect fit but a high quality 550W can do it.

 

[Tormidal]

Graphics card are power hogs. PCPartpicker and PCSpecialist are estimates, when the graphics cards are under a load, they use more power than they normally would.(e.g.; it needs more power playing Watch Dogs than it does playing Minesweeper.).

With this in mind, as Asus says, its recommended that you run a 750 watt power supply, to ensure that if, for whatever reason, your graphics card is pulling more power than it should, it wont crash your whole system, as well as powering the rest of your system.

PC Specialist is right that the minimum the system needs is 550w, but it rarely calculates how much it would need under a load due to the number of variables that would be involved.

I would recommended going with what the manufacturer says you should - in this case; a 750W.

 

[Dark Lord of Tech]

If you want a steal on a top tier PSU made by the best Super Flower.

Semi-modular.

PCPartPicker part list / Price breakdown by merchant

Power Supply: EVGA 750W 80+ Bronze Certified Semi-Modular ATX Power Supply (£66.60 @ Aria PC)
Total: £66.60
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2014-09-23 23:31 BST+0100