GeForce 9800 GTX - No Signal Monitor

Hi,

I recently purchased a GeForce 9800 GTX and although it would register my monitor before, it doesn’t appear to be doing so since last night. The video card fan is running and the green LED lights up when i plug the monitor in… but im receiving no signal. What could be causing this?

I have a 610 watt PSU, and a 22’’ widescreen Acer

What are your full specs?

My rig

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Nvidia Geforce 9800GTX
Intel Core 2 E8400 3.0 GHZ Wolfdale
Seagate 500GB 7200 RPM SATA
Corsair 2 x 2 GB DDR2
610 Watt PSU
Asus NVIDIA nForce 750i SLI mobo
Antec 900 mid-tower
Acer 22’’ Widescreen