hi I am going to be purchasing a 7870 XT card and I am confused about the power usage. On pcpartpicker it claims the wattage used will be around 366W, and that would seem fairly accurate but on the product details for the gfx card it says a 500W psu is required. I don't think it will ever use 500W.. but I have no idea. seems very high to me. I was going to get a 550W psu but I don't know how much the card will use under full load, and if I'll need a bigger PSU. Thanks for any info in advance
Don't worry, your psu can handle it. And you're right, you probably won't pull 500W at any point but having the headroom is always a good idea since power supply do degrade over time. The reason why AMD (or Sapphire) says the card requires a 500W psu is because they considered people using cheap, low-end psu that does not output power as actually stated.
as i understand it 500w is what required for whole system, not one part of it( gpu in your case)
Yes 500W is the total for the system but the 2 biggest draws is the graphics card and the cpu which is why alot of people will give the power supply recommend based on the graphics card draw and assume 75-125W for the CPU.