do you mean 5477?  if yes it has HDMI in and HDMI out.  you can use another laptop that has HDMI out to send video to the 5477 HDMI-in to test screen, and you can use 5477 HDMI-out to connect an external HDMI monitor.  the purpose of this test is to differentiate screen issue vs video adapter problem. If screen has problem but video adapter is good, 5477 HDMI-out would give normal video on external monitor.  and laptop HDMI out video would reproduce artifact on 5477 screen. oth if screen is good but video adapter has issue, 5477 HDMI-in would display normal video from laptop, and HDMI-out would replicate artifact on external monitor.
Very thin red, blue and green vertical lines appear on my display (always on the left side in about a 2" wide area on my Inspiron all-in-one 5744 A10 Series desktop.  Please help!! Bclif1
Very thin red, blue and green vertical lines appear on my display