I suddenly got a 'Check Signal Cable' after turning on my monitor. It was working this morning I checked the vga cable. Inserted it to another monitor and it worked I have a

Samsung S19A300B Radeon HD 4670 asus mobo and a pentium dual core e5300

i tried using other cables but it just displays "check signal cable" and 3 boxes with red green blue colors and a "Digital" just below it :|

2 Answers 2


It sounds like it's trying to use the DVI input for your computer instead of the analog VGA input that you want it to use. Some monitors try to autodetect this, while others you have to manually set. Is there a button on the monitor to switch inputs? You may also have to go into the monitor's menu to do this. I tried to find the manual for your monitor, but the product page on Samsung's website appears to have been taken down.

  • actually the monitor has 2 inputs one for the dvi and one for avg .same for my vcard May 5, 2011 at 2:22
  • Right - What I meant was the monitor is looking for input on the DVI connector instead of the VGA connector.
    – Dan Walker
    May 5, 2011 at 3:40
  • Thanks, you helped me.
    – Or Assayag
    Jul 30, 2021 at 12:00
  • This! I'd say most monitors do this automatically though. I have 6 different monitors, just one didn't doesn't do it automatically. Jun 18 at 13:53

I had similar issue: the monitor showed HDMI with five dots, and then analog with five dots and then it went to black screen with blinking red light.

To solve this: I downloaded the latest firmware for my monitor from the samsung website and restarted my computer and everything worked like a charm. Note that I installed the firmware from windows 7. It started working on Linux as well, I did not have to do anything for it !

  • Yes, this worked for me. My s24a300bl stopped working after a few weeks of disuse. Windows identified it, but I just got the "Check Signal Cable" message. After installing the newest firmware, it works fine.
    – jdm
    Nov 11, 2014 at 10:12

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