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Question

I need a big help about a big HDMI problem

Aug 10, 2018 3:50PM PDT

So, i have a relly strange problem with my VGA/HDMI:
1. I have two HDMI inputs in my TV/Monitor but the video can be outputted in only one of them
2. The video quality is really bad: it's very pixelated bright and the colors are all wrong
3. If i start the PC in safemode in 1024x600 (or something like that) the "non working" HDMI will start working, but if i switch the resolution back to 1080p it will stop working
4. This HDMI will work if i use the CPU integrated graphic
I have a R9 380 by XFX with latest drivers installed and my TV/Monitor is a Samsong T24D390.
Is there something i can do to solve this problem? Thanks for the attention.

Discussion is locked

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Answer
Sounds like it needs repair.
Aug 10, 2018 4:20PM PDT

I checked the user manual and from what you are writing the TV sounds defective.

Since it never worked right (you didn't write it ever did) I'd return it for a good one.

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Forgot to mention
Aug 10, 2018 4:51PM PDT

I'm sorry, i didn't specify, I have had this monitor for more than a year, everything was working just fine till the other they, then from a moment to another HDMI 1 stopped working, and i forgot to mention that sometimed the "non-working" HDMI starts to work again, but if i play a game in full screen then close it, cahnge the resolution or alt-tab from a full-screen app, it will stop working.

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in this day and age of hotpluggability ...
Aug 10, 2018 7:13PM PDT

... we sometimes forget that hdmi seems to be the odd one out. Instruction booklets usually tell you to only plug your hdmi components together when powered off. I know we normally take our chances with that, but I have seen a few cased where it just wouldn't sync. Your story of "now it works and now it doesn't" sounds a bit like that ...

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Read other ideas.
Aug 11, 2018 10:04AM PDT

Try the other HDMI port and other cables. Test this TV with some DVD/BD or other HDMI source.

Be sure to remove HDMI cables and power from the set so the HDMI chips and such reset.

Then test again.

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Answer
Sync devices and/or replace hdmi cable
Aug 10, 2018 8:36PM PDT

Hi, let's consider some alternative issues:
1. The settings between the PC and the monitor are not in sync.
2. Hdmi cable needs replacing.
3. The monitor's ports are damaged, or the PC port is damaged. These last possibilities are very unlikely - you'd have to visit a Best Buy or somewhere similar to have them tested. It is much more likely the issue is #1 or #2.

(#1) When you look at your PC's resolutions, one is marked "Recommended". Set your PC on that one, and then do a Restart. I checked your Samsung monitor's user guide, and it does require the "Recommended" resolution. You can download the user guide from here, and read up on this further: https://www.samsung.com/us/support/owners/product/led-monitor-sd390-series
In general, read up on all the monitor's settings, in case another setting has a similar issue syncing with the PC.

(#2) Try replacing your hdmi cable, because they do go bad after awhile. I would recommend an AmazonBasics high speed hdmi cable. Whatever brand you buy, make sure it says "high speed" - otherwise you are using an out-of-date hdmi standard. Attach the new cable as follows:

a. Plug cable into monitor, then turn on monitor.
b. Turn on PC and wait till it's fully "up".
c. Now plug the other end of the hdmi cable into the PC. The PC's picture should now be visible on the monitor.

Let us know if this helped!

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Followup
Aug 11, 2018 9:57AM PDT

Oops - I gave you the wrong link for the user manual. I've gone into Samsung three times now and arrived at three different links! Check whether your T24D390 (= TD390) has a suffix at the end such as T24D390S, then look for the user manual on the official Samsung site.

However the advice remains the same - try #1 and #2 before doing anything else. A regular high speed hdmi cable should work fine. Best wishes.

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Answer
User's Guide shows HDMI 2 is an MHL over HDMI port
Aug 10, 2018 11:10PM PDT

The user's guide for the Samsung T24D390 shows HDMI 1 as a DVI over HDMI port (no audio) and HDMI 2 as an MHL over HDMI port. MHL is a standard to mirror a (mostly Samsung) smartphone screen. An MHL cable is micro-USB to HDMI. That port probably can't handle a regular HDMI output. Get an MHL cable and try connecting your phone to it.