they say it coz a lot of people use low quality power supplies which have misleading information on the real wattage of the psu.
however your psu will run it just fine. i myself run a 7750 on a 350 watts coolermaster elite with no problems
It's blinking of the lower 1/3 or half of the Dell U2713HM display, lasting about 1 min, with different intervals; sometimes longer, sometimes shorter, ~5-10 min. Now I take out the GT620, using the integrated Intel HD 2000, never blinks. I'll try to upload some video later. Thanks a lot!
GT 620 consumes less power than HD 7750. Also, it should run on your computer without any problems. Could you describe the "blackouts"? We could maybe resolve them.
The only real alternative that uses less power is GT 610.
It's a DVI-D male cable coming with the 27' display, connecting a DVI-D female on the display and a DVI-I female on GT620, that shouldn't be a problem, right? I've returned the card to newegg, will try some other ones...that's where I need some suggestion.
On p7-1380t page, it says:
Must select one of the following options:
Intel Graphics Media Accelerator HD Integrated Graphics
GeForce GT 530 (2 GB)
GeForce GT 620 (1 GB)
GeForce GT 630 (2 GB)
GeForce GT 640 (3 GB)
Radeon HD 7350 (512 MB)
Radeon HD 7450 (1 GB)
Radeon HD 7570 (2 GB)
620 is one of those...perhaps it's indeed a bad card. How about AMD HD6450? Those fanless GC should require lower power supply, right?