Odd screen problem - Resolved

So i just moved my current pc which is a amd athlon 3700+ with 2 gb of ram into my bro's pc, and bought him an 8400 GS with 256 mb ram graphics card. He was complaining his current pc (p4, 1.7 ghz, 512 ram, 5200 fx) was too slow, so i decided to give him mine since im building a new one in the next 2 - 3 weeks. I got it all set up and running with windows xp pro. in my room. The resolution was at 1280 x 768 in my room on my monitor, and it was perfectly fine, but when i brought the pc to my brothers room ( he has the exact same monitor as me) it flickers every few seconds at the same resolution. When i turn the resolution down it does go away, but he insists on having the largest resolution it can have.

I can't figure out why it worked on my monitor but not on his since they are exactly the same. It flickered in my room with the dvi to vga adaptor, but once i removed the adaptor it works perfectly fine, atleast on my monitor, but my brother's just flickers constantly. Need some help please.

 

Problem has been solved, turned out to be that VGA cable went bad, didn't even know that was possible. Don't see any pent pins or anything either, but the cable had tension, as the desk we use the screen and pc are a fair distance apart, and the cable is short. Now using my pc's VGA cable as my pc is out of order, and i plan to get myself a new cable. Any idea if you can get VGA extensions?

 

VGA extension cables do exist, I think I have one somewhere that is 1 - 1.5m long.

 

Since i dont have my pc at the moment i took my vga cable, drilled a hole through his desk so instead of running wires behind we could run straight up, no more tension. I'll get a dvi to vga cable as for some reason my hdmi screen wont work properly with my hdmi cable, and i know both my gpu (8800 Gt) and monitor support it as i read it supports 1080 and has the plug for it.

 

Is the HDCP signal sent if you use a HDMI>VGA adaptor? You can't get 1080p otherwise . . .

 

I have no idea what that means, i had a dvi to hdmi cable that i used... plugged the dvi into my 8800 GT and the hdmi into the monitor, it worked but the resolutions were all wrong even though i set them up and everything... I plan to try again once i get my new parts on monday