How many watts does my Computer need?

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1

Was looking at the websites that you put it your specs and it estimates how many you need but one said 300 and another said 500. What do you guys think, specs:

ASRock Z77 Extreme4 Motherboard

G.Skill Ripjaws X F3-12800CL9D-8GBXL (2x4GB) DDR3

ASUS GeForce GTX 670 DirectCU II

CoolerMaster HAF 912 Advanced

3 Xigmatek XLF-F1253 120mm LED Fans

Intel Core i5 3570 (Not overclocking)

Seagate Barracuda 2TB ST2000DM001

Samsung SH-224BB/BEBS SATA DVDRW Drive OEM

thanks for reading/replying

2

hmm, I would go with a 600 watt just to be safe

3

At the moment ive got my eyes set on a 750w psu its a little expensive, do you think I should go lower or stay at 750?

4

750 would be a good comfort zone for future upgrades

5

Okay mate thanks for your help im new to this stuff

6

not a problem. That's what this community is about! I'm often working on videos for my youtube channel as well as helping people on here when I can