Do I need a new PSU?

[johnsmith1212]

Recently, my computer suddenly shut off on me after showing signs of lag. I tried unplugging and replugging everything in and it worked again. However, I recently got my RX480 graphics card and plugged it in. Everything turns on, I hear the drives boot up, fans turn on, but my screen remains black. I checked a power usage calculator and it comes out as 379W so my 500W PSU should work. I then unplugged the PCI-E cord from my graphics card and it boots up again. Does this mean my 500W power supply is not enough?

This is my build:
i5 4690k processor
2 Kingston HyperX Fury 16GB Kit (2x8GB) 1866MHz DDR3 CL10 DIMM (HX318C10FBK2/16)
MSI Z97S SLI - Krait Edition motherboard
Case is one of those Be Quiet! ones with 4 fans
Thermaltake 500W power supply

Thank you in advance!

[Wijkert]

500W should be plenty for your rig. Those calculators are usually on the conservative side. Have you tried unplugging everything but the essentials to pinpoint what the culprit might be? Also, it seems that you have been issues even before you got your RX480; which might point to the fact that some other component was dying already. Do you have a second rig, so you can to test stuff by exchanging components ?

We might be able to give you some pointers like I just did, but I feel you would be better of posting something like this on the overclock.net forums.

[scavvenjahh]

Maybe that sudden shutoff was caused by or caused some damage to the PCI-E port... and the 480's notorious PCI-E power draw is only making things worse. Try plugging the card to another port.

[Haldi]

Download and install FurMark and Prime95.
Run both at once.
If your system crashes your PSU can't handle the load and something is wrong.