DVI cable broken, too long, or need booster?

[RunnrX]

Hi guys,

I've got a Radeon HD 5450 running a DVI out to a 22" LCD that takes DVI-D input

the cable I'm using is an Ultra 50foot long dual link DVI-D cable so it can reach across a store I work in as a display for customers to see

if I use the 3' long dvi cable the montior comes with I get a signal, but with this brand new 50' cable right out of the box (or off the coil in this case) I would get an image for 1-2 seconds, then a black screen, then 1 second image, 1 second black, until eventually just a black screen

it is the cable for sure - question is, is the cable broken, does the connection need a DVI booster or repeater because the cable is so long, or (noob question) does the video card need a better output somehow via stronger computer PSU?

Thanks guys

[yudah]

try good quality cables you may need inline booster/repeater

[liljim]

your problem can actually be a combination of things, cable quality, video card quality and monitor quality. Narrowing it down to just one is a pain but its more than likely signal loss in the cable. Its not out of the ordinary to start having problems after 15-20 feet.