Bad video card?

Hello everyone!



So, here's my problem: I've just bought a new video card (been using the onboard Intel graphics until now) and PSU. Every time I push the start button, the PC keeps reseting itself after a few seconds. Sometimes it makes it to the POST screen and then rebootsor just hangs there, sometimes the screen stays black and I can hear the login sound. After about 5-10 reboots, it starts up and everything works fine. I tested it in games and 3dmark and it works flawlessly, which makes me think that the PSU is not the issue here.



It also boots just fine with the onboard graphics, as long as the video card is not installed, but reboots if it is. The video card supply cables are ok (the card has LEDs that show if the cables are plugged in correctly). The fan speeds, voltages and temps are more than ok. I also tested it with an old video card and it booted up without any glitches.



System:

Gigabyte Z87MX-D3H

i7 4770K

Crucial Ballistix 2x8

1 SSD, 2 HDDs

Asus 280X CUII Top

Antec Truepower Classic 550W



OS: Win 7 64/Ubuntu 14.10



It'm guessing it's the card, but I wanted to make sure before I send it back. Any help will be appreciated. :)

Bad video card?