Gtx 570 + dual monitor = Sleepmode

[Moofrad]

Hi

I have an gtx 570 and when I plug in two monitors and start my computer both monitors fall into sleep mode. this has happened several times, sometimes the problem is solved by disconnecting one monitor and connecting it with a HDMI. Otherwise I connect both monitors to the card with DVI.
Why is the card puuting the monitors into sleep mode when I plug them via DVI?

(Has happened occasionally that the screens fall into sleep mode even when I connect one with HDMI and the other with DVI)

first monitor is a Dell UltraSharp U2711 and the other is a LG Flatron W2442PE

My computer spec:

Asus P8P67 PRO REV B3, 1TB Samsung Spinpoint F3 HD103SJ, hardrive2:Corsair SSD Force Series 120GB 2.5"
Processor: Intel Core i7 2600K 3,4GHz, Noctua NH-D14, mem: Corsair 8GB (2x4096MB) 1600MHz VENGEANCE
GPU: Asus TX570 DCII/2DIS/1280MD5, Case:Fractal Design Define R3
Corsair TX 850W V2 80+ Bronze On a Windows 7 Pro 64

sorry if my english is confusing

 

[dazer]

Well i dont no the solution but im also having the same problem with my LG monitor, Trying to use 2 monitors and it instantly goes into POWER SAVING MODE. Seems alot of LG users get this..