Getting ‘No signal’ on your DisplayPort? Here’s a fix

DisplayPort-logoWhen I got a new desktop computer I ran into issues with DisplayPort. My screens worked just fine (even in UHD, albeit at only 30Hz.) with the DVI cables, but when I’d hook them up with DisplayPort cables, I’d get a ‘No signal’. For some reason, this only occurred with 3rd party DP-cables. The cable which came with the screen did work but was too short for my needs.

The 1st set of 3rd party cables I returned because I thought they were defective. As a replacement, I ordered 2 different DP-cables. When both of those didn’t work for me either, I resorted to Google for answers. And that’s how I found the solution: Unplug your screens for a minute from the mains! (Merely turning them off/on won’t do the trick. Apparently, there’s one/more capacitor(s) which needs to fully discharge.

Since I don’t want to go through the hassle of physically unplugging my screens between use, I enabled the EcoControl feature on the UPS to which the PC is connected. As soon as it notices the PC (master) is switched off, it cuts the electricity to the screens (slaves).

After I did this I haven’t had any problems any more with my displays.

No guarantee this will work for you if you experience ‘no signal’, but it’s worth a try 😎

My hardware:

PCDell Alienware Area-51 R2
displayAOC U2868PQU
UPSEaton Ellipse ECO 1200 DIN

64 thoughts on “Getting ‘No signal’ on your DisplayPort? Here’s a fix”

  1. Pingback: no hay señal dp de su dispositivo - Portal Login - Your login web pages

  2. What the actual ****. This worked for me after my monitor suddenly stopped working on DP. How’d you find out and why does this solve it?

  3. I’ve had this issue for months, to which it happens once every week or so. I had firstly thought it was faulty cables and kept trying different variations.
    I tried this one time and it worked perfectly… I wish I knew sooner! I had tried switching the monitor off for a while and even unplugging the power from the monitor ONLY, however not unplugging the mains from the wall, which does work.
    I have the AOC U2868PQU 28″ 4K monitor and an NVIDIA GeForce GTX 980.
    Thank you for the fix!

  4. So dumb that this is still a problem 2 years later. Solved it though.
    notes for my system had this problem with my new GTX1080 and my monitor was a benq 2420pt.
    turned them off at the wall for 2 minutes back on worked straight away

  5. Thank you so much for this solution i tried everything but did not expect killing the power would work but it did so thanks again for this solution.

    1. Just wanted to note that my GPU is an older NVidea GeForce GTX 960, Windows 10, Dell monitor set to 2560 x 1440.

  6. Brilliant! Worked perfectly. Now I wonder what I did to set it off. No problems since I bought it years ago.

  7. worked on my AOC2770G4 monitor with my Nvidia GeForce GTX 760. Just unplugged my monitor for a minute and boom, back to 144hz DP ooohhh yeah. Spent 20mins trying different things before resorting to some googling

    thanks very much OP

  8. I am surprised that it worked. I tried changing cables, adding adapters, removing and installing all relevant drivers, and what not. Nothing worked. Never thought detaching and attaching power and DP connector will work. 🙂 FYI for those in need, I tried this with Alienware 15R3 + ASUS VG248QE.

  9. Yep, that solution works great. We have 3 identical computers at work that all have exhibited this behavior over the last few months. That’s all it took to fix all 3. Seems to be a fault in the DisplayPort spec? Thanks for setting us straight.

  10. Rudolf van der Berg

    We had a similar problem here. I’m the only one who uses Displayport to connect to our AOC 2560×1440 Q2577PWQ. Colleagues with HDMI have no problem. Me, sometimes when I show up in the morning, I am faced with the monitor just not turning on. No monitor, no blue or red led, just pure blackness. First time we sent the monitor back. It was only after two days of operation. Second time we changed the power source,we unplugged the displayport cable from the laptop, nothing worked. Then my colleauge shifted one of the unused screens to me, I connected the Displayport cable and the new monitor worked great. My colleague then fiddled with the faulty screen by plugging it into electricity in and pressing the power button for a couple of seconds. A blue light popped up and it worked again.

    What we found after multiple incidents and verifying is that the solution is to unplug the displayport cable from the monitor. Unplug the monitor from electricity (take out the cable). Wait a bit, long press the power button, reconnect everything and it works again.

    1. Similar problem here solved. Using an Asus B85M-G motherboard with an Intel G3258 CPU. Installed the NVS310 dual display port video card and connected two monitors using display port to HDMI cables. Long story short, the motherboard BIOS had to be set to use the PCIe slot for the primary display, the driver had to be downloaded and installed, and one of the two cables being used was bad. I bought two cards and four display port to HDMI cables. I always do that the first time I use something. I will be returning one of the cables.

  11. Thanks very very very much for this, like all the other posts this problem has plagued me since i got an aoc u3477. sometimes it’d come on sometimes not, i used to leave it in sleep mode (the pc) and that worked most of the time but sometimes not, and i’d boot with hdmi which was fine, bought 4 dp cables.Thankyou so much from the bottom of my heart lol

  12. And we have a winner! Suddenly screen connected to my laptop stopped working. No signal. Took it off the power and back on it again and all fine now.

  13. I have got new monitor, the asus rog swift PG248Q and am having same problem with ‘no display port signal’ – I tried the tip here but no still joy. I’m not very tech savvy so unsure if the problem is my desktop PC or the monitor. The HDMI works fine but I got this for the G-sync but it wont work on HDMI, it needs display port to get full benefit. My desktop doesn’t have CD rom drive, so I can’t install the drives from the disk. I’m not sure where the problem is….Any suggestions?

    1. Hello mate, I am having the same issue here. I have PG248Q too and also my monitor is not getting signal even with HDMI.
      How did you find the solution?

  14. I know this sound stupid, but it actually worked. I have tried to reinstall the system, update my drivers and even replace my display port cable. None of them worked. And then I found this gorgeous post, unplug all the power and waited for couple minutes. When I start my computer my second screen works again!!

  15. thank you. such a simply solution. gtx690, dell 3011 and accell displayport cable as pin20 is cut.

  16. A very Huge Thank you. was trying for 2 hours changing leads, uninstalling drivers changing graphic cards…… A simple case of turn it off and on again Works ! 🙂 well happy. Cheers.

  17. THANK YOU!!!!! I was considering purchasing a new monitor – simply unplugging it fixed it! I am using a DP to VGA dongle so I just thought it would not work.

  18. Thank you! I researched a switched cable and found it! It’s a “switched C14 to C13 cable” like ebay item 201629171936. It’s easy on/off and no need to plug/unplug.

  19. Thanks for this Evert. I had the same problem with my AOC U3477PQU. All I had to do was unplug the monitor and leave it for a couple of minutes! Such a simple fix. Regards, M

  20. Thanks very much. This seems to be a common problem for AOC-Displays. I have a AOC G240PF. I never noticed the problem before since I kept unplugging my wholy system if i didn’t use it, Just didn’t do it yesterday….

  21. Thank you good sir! This has been a massive help when this first happened to me, again thank you!

  22. Found this when searching for a solution to a similar problem with my setup. I have two Asus PB287Q 4K UHD monitors, 1 – 32″ HDMI TV, and 2 – 23″ DVI connected monitor on my rig. 5 monitors in total. 2 – 4K monitors are connected to a GTX 980 Strix Nvidia GPU and the two DVI Monitors are connected to a GTX 750ti. One of the 4K monitors refuses to work on display port. I swapped cables and nothing I have done has fixed the issue. the other twin 4k monitor works wherever you plug it in and the HDMI port works fine at 3840×2160. Going to try the power down idea and see if it helps otherwise its RMA time. Great way to start a Monday!

    1. I managed to get the Display port working again on the problem child monitor. Ended up hooking up a HDMI cable, going into System setup > DisplayPort Stream .and setting the option to 1.2. This managed to bring the display port back to life again. FWIW I could not get into System Setup without connecting the HDMI cable. There was simply no options available to me on the menu, with display port not working. I tried the power down method for a couple minutes to no avail. Hopefully this helps someone else that might have the same issue.

  23. You blessed man. I had the exact same problem. I searched for many other solutions but this one solved it!! I was so confused. at first I though “no way my gtx 980 just crapped out. Thank you!

  24. Same problem all the time aoc 28 etc gtx 980 ‘s always having to do this all the time unplug n plug back in any news on a fault with these monitors?

  25. Holy crap. Can’t wait to try this when I get home. I’ve been through so many cables, driver updates, bios updates, ATI firmware updates… forcing unsigned AOC drivers… updating DisplayLink drivers… etc.

    I really hope this works. AOC U3477 here

    1. Well, it kind of worked. Still can’t get DP to work in 3440. On my second set of monoprice DP cables. Just purchased another brand on Amazon with high hopes.

  26. LEGEND – I also have AOC U2868PQU 28″ 4K Monitor and Nvidia GTX 960 4GB. I’ve had problems intermittently with display port not working but recently it would not work on display port at all (HDMI was fine). Tried all sorts to fix it then stumbled across this – worked a treat. Thanks OP.

  27. Thanks dude. First i tried going to nvidia control panel and selecting the monitor, but it would never work. but after that I Turned off my computer for about 5 minutes and it was still a black screen. but the nvidia control panel started working. Thanks. if this didnt work for you go into your system settings and try that again

  28. Same thing with my Asus PB287Q Display.
    I probably fixed it, can anyone check this out please

    Power options (control panel – system and securety)
    PCI Express : Link state management – Turn it of.

    It works for me at the moment.

  29. DUDE!! You are my friggin hero!!! I have been trying everthing from Bios updates to cable and hardware swaps and this 1 minute of effort actually works! I was getting no displayport to my ASUS 248qe monitor after upgrading to an R9 390x. Couldnt figure it out for the life of me after a clean driver install and the other things mentioned. I simply unplugged the Displayport cable and power cord with the system was running and plugged them back in about a minute later. My ASUS monitor came right up at 800×600 resolution. I changed the res and refresh rate via Windows and bingo!! works great! I cannot thank you enough!

  30. Matthew Goldsmith

    Had the same problem with an AOC 3440×1440 this solved it! I’m a little dissapointed with this screen and this issue as its a very expensive screen, i expected better.

  31. Same thing… Brand new AOC U2868PQU 4K monitor and all of a sudden there is a ‘No Signal’ on startup.
    I used your advice above and physically pulled out the power cable from back of the monitor and left for 10-15 minutes. Voila – Monitor comes back on after that – so definaltey the Capacitor in the monitor.
    Might try to contact AOC on this as I consider this a manufacturing fault.
    I have just heard the manager at the computing store I bought this from has the same monitor, and has had it replaced twice but each monitor still has the same issue.
    Thanks for the workaround, at least it got me out of trouble on a production day.

    1. Just an update: This loud ‘electrical pop’ then monitor blacking out on my AOC U2868PQU kept occurring. Pulling out the power cable each time to fix became a real pain and I worried was damaging the life of my monitor (as well as making me jump every time it blacked out). Different power cables didn’t help. AOC ended up trying a firmware upgrade where I had to send the monitor back (no replacement offered while it was with tech support) but when it came back the problem still occurred, but just not as often. As it was still under warranty, they replaced my monitor with a ‘new refurbished’ monitor and it hasn’t happened since. I definitely think there is a batch of monitors out there with faulty capacitors. Because the replacement worked fine, I have since bought the newer version Model AOC U2879VF and that has not had a single issue. Running these two screens side by side is brilliant! Hope that info helps someone.

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.