Extremely annoying acer monitor problem

So I received a new monitor about a week ago and everything about it is great, except one thing: occasional problems opening up videos.

Sometimes when I open up a downloaded video, the monitor will just turn to...

(Sorry it's upside down)



You can see that I (blindly) dragged the video to the other screen I have, and it's fine. I tried turning off the monitory, but no, it still has it. I switched input and it goes away, but I go back to my pc and it's there. This doesn't ALWAYS happen, but it happens enough to be extremely annoying. I'm on windows 7 and my specs are below. Please help?  

Monitor


PCPartPicker part list / Price breakdown by merchant / Benchmarks

CPU: Intel Core i5-3570K 3.4GHz Quad-Core Processor ($169.99 @ Microcenter)
CPU Cooler: Cooler Master Hyper 212 EVO 82.9 CFM Sleeve Bearing CPU Cooler ($24.99 @ Newegg)
Motherboard: ASRock Z75 Pro3 ATX LGA1155 Motherboard ($84.55 @ Newegg)
Memory: Corsair XMS3 16GB (2 x 8GB) DDR3-1600 Memory ($73.15 @ NCIX US)
Storage: Seagate Barracuda 500GB 3.5" 7200RPM Internal Hard Drive ($59.00 @ Compuvest)
Storage: Western Digital Caviar Blue 1TB 3.5" 7200RPM Internal Hard Drive ($69.99 @ NCIX US)
Video Card: HIS Radeon HD 7770 1GB Video Card ($131.97 @ Newegg)
Case: Antec Three Hundred Two ATX Mid Tower Case ($59.71 @ NCIX US)
Power Supply: PC Power & Cooling Silencer MK III 500W 80 PLUS Bronze Certified ATX12V Power Supply ($64.58 @ NCIX US)
Optical Drive: Samsung SH-224BB DVD/CD Writer ($22.98 @ Newegg)
Other: Seagate Barracuda 320GB 3.5" 7200RPM Internal Hard Drive
Total: $760.91
(Prices include shipping, taxes, and discounts when available.)
(Generated by PCPartPicker 2013-01-11 17:09 EST-0500)