Computer can't detect screen resolution options for my (third) monitor and has it stuck at 640x480 - please help :)

[juddr]

Hi,

I'm trying to connect up 3 monitors to my computer. Two are working fine: the third monitor isn't. The computer (or monitor?) is only detecting that monitor at 640x480 resolution.

By which I mean, the screen resolution option for that monitor is greyed out.

Here is an imgur-uploaded screenshot of all three monitors with the Windows Screen Resolution, well, window, showing. It has a red box around the greyed out screen resolution option for the third monitor.

I am at my wits' end with this (this is the latest in a line of problems trying to get this set up to work). I find monitors and displays very confusing - and would very much appreciate some help, if you can, or have any ideas!

Here's some info on my set up:

• 
  ■ graphics card is a Radeon HD 6700 series. I just updated the drivers and it hasn't fixed the problem.
  ■ monitors #1 is a BenQ 27" displaying at 1920x1080, connected via dvi (working fine),
  ■ monitor #2 is a 17" acer displaying at 1280x1024, connected to a dvi to vga adapter (working fine),
  ■ and monitor #3 is an LG 22", connected to the computer via an hdmi cable with an active display port adapter. The LG is the one that is displaying at 640x480. Before Christmas I had it in a 2 monitor set up with the 17", and it had no problems finding other resolution options then.
  ■ Operating system is Windows 32 bit.

Here's what I have tried (updating as I try suggestions):

• 
  ■ I have tried updating the graphics card drivers. No dice.
  ■ I have tried disabling the 17" monitor to see if the computer/24" monitor then decide to find other resolution options. It doesn't make a difference. The resolution dropdown box is still greyed out.
  ■ I have tried googling, but I am getting very confused and don't know whether to focus my search on the 3 monitor aspect, the greyed out resolution options aspect, or what.
  ■ Edit: suggested to try this "use amd catalyst to fix the screen resoultion not windows should work" - did so, does not work.
  ■ Edit: Suggested to switch the cables around between the 27" and the 22". Please see reply below for details on what happened.

Please help if you can, I'd really appreciate it.

Edit: it also seems that the computer can't detect what sort of monitor the 3rd screen is. For the 27" and the 17" it lists their model numbers in both Windows screen resolution management and in the amd control center. However, for the 22" it calls it a "generic non-pnp monitor" in Windows resolution management, and simply "unknown" in amd control center.

Update:


At this point (due to the cable trial which I typed up in a reply below), I'm wondering if we have a faulty cable - the hdmi cable (with active display port adapter) that the 22" was originally plugged in with, which I have just tried with the 27".

It should also be noted that originally today we tried a completely different hdmi cable with the active display port adapter and 22" monitor, and that resulted in nothing at all being displayed on the 22". Assuming a faulty cable in that instance, we found another hdmi cable - the one currently being used - put the active display port adapter on that, plugged it into the 22", and here we are with it displaying 640x480 on apparently 2 different monitors. (This would however make it two different hdmi cables thought to be faulty, which maybe casts doubt on this cable being faulty as well.)

The only other things I can think are that my graphics card isn't working with it (but then why would it only display at 640x480 with only 2 monitors connected and this cable being used) or the brand new active display port adapter isn't agreeing with the setup somehow.

Or is it something else? Further thoughts welcome!

PS Although I've tried updating my graphics card drivers, is it worth trying to update to the beta drivers?

 

[nickbachu]

use amd catalyst to fix the screen resoultion not windows should work

 

[juddr]

use amd catalyst to fix the screen resoultion not windows should work

Thanks for the idea! However, amd catalyst control center can't seem to find any other resolutions either.

Here is another imgur'ed screenshot showing that the resolution option for this monitor is also greyed out in the amd control center.

Unless I am in the wrong bit of the control center? I find its ui very confusing. I am in desktop management -> desktop properties. Is that right or should I look somewhere else?

Otherwise, if I have done this right - do you have any other ideas?

 

[nickbachu]

try switching the cables with the second monitor and see if it works to let you fix the resolutions

 

[juddr]

Thanks again!

try switching the cables with the second monitor and see if it works to let you fix the resolutions

I tried switching the cables between the 27" and the 22".

Result of doing so:

The 22" worked fine. Correct resolution. The 27" now had the 640x480 resolution with no option to change it + resolution box greyed out.

You can see here in this picture that on the resolution options page, the middle monitor (the 27") is now the tiny one, and the right one (the 22") is now a more normal size. That picture also shows that the 22" resolution options are working correctly.

This picture has the 27" highlighted and shows that the resolution options are greyed out.

I tried going into the amd control panel and setting the resolution there under display properties. Once again, it was greyed out here as well (now for the cable-swapped 27").

Also, the computer now read the 27" as "generic pnp monitor" and/or "unknown" in Windows resolution management / amd control center respectively - like it was doing with the 22" when that was plugged in with this cable.

Lastly for this update, I unplugged the 22" in preparation for switching the cables back around again. Before I did any more cable switching, I checked the 27" again. It still was stuck on 640x480 (this picture shows only 2 monitors plugged in, and one of them - the 27" - with the resolution option problems). Now I have put its original cable back in, it's back at proper resolution.

I have updated my original post with some ideas on what might be going wrong, although they're really just ideas in the dark - I'm not sure if it could be one of those or something else entirely?

 

[nickbachu]

as im seeing it is the cable do you have a spare cable to try with this might fix the problem

 

[juddr]

as im seeing it is the cable do you have a spare cable to try with this might fix the problem

We have 2 hdmi cables and have tried both of them. When we used the first cable we got no picture at all, hence using the second hdmi cable - the one we're using currently, while having this 640x840 / no resolution options problem.

I guess it could be that we have 2 faulty cables with different faults. We don't have a third hdmi cable. However, we're now buying another one from Amazon (this one, for reference) and expect it to turn up on Thursday for testing. If it works - great - if not, we have another spare hdmi cable and we're back to the drawing board.

I will update again once the new cable has arrived and we have tried it.

Thanks for staying with me on this so far

 

[AdioKIP]

It sounds like you have a bad displayport Adapter. I had the same symptoms when my original adapter died. AMD cards (especially the older ones) can often be picky about which Display Adapters they work with. I would highly recommend you try another adapter.

 

[juddr]

It sounds like you have a bad displayport Adapter. I had the same symptoms when my original adapter died. AMD cards (especially the older ones) can often be picky about which Display Adapters they work with. I would highly recommend you try another adapter.

Thanks for the input! Are there any particular adapters you'd recommend?

This is the one I'm using at the moment (link goes to Amazon UK). The packaging says it has a 2 year warranty... the adapter was brand new this morning but I guess I could have got unlucky and received a dud!

 

[AdioKIP]

I've seen people have problems with the startechs. I would recommend one like this that specifically mentions being EyeFinity Compatible.

http://www.amazon.co.uk/Active-DisplayPort-Link-DVI-Eyefinity-Adapter/dp/B00439G3NW/ref=sr_1_2?ie=UTF8&qid=1389189017&sr=8-2&keywords=his+displayport+adapter

or

http://www.amazon.co.uk/Sapphire-44000-02-40R-Active-Display-Cable/dp/B00433C5Y4/ref=sr_1_3?ie=UTF8&qid=1389189344&sr=8-3&keywords=EyeFinity+displayport+adapter

All the ones I've seen work well go to DVI. If you need HDMI like your previous adapter, just use an HDMI to DVI cable. Even if you dont go with this exact adapter, I would try one that is from a manufacturer that sells AMD cards (HIS, Sapphire, Visiontek etc..) .

 

[juddr]

I've seen people have problems with the startechs. I would recommend one like this that specifically mentions being EyeFinity Compatible.

http://www.amazon.co.uk/Active-DisplayPort-Link-DVI-Eyefinity-Adapter/dp/B00439G3NW/ref=sr_1_2?ie=UTF8&qid=1389189017&sr=8-2&keywords=his+displayport+adapter

or

http://www.amazon.co.uk/Sapphire-44000-02-40R-Active-Display-Cable/dp/B00433C5Y4/ref=sr_1_3?ie=UTF8&qid=1389189344&sr=8-3&keywords=EyeFinity+displayport+adapter

All the ones I've seen work well go to DVI. If you need HDMI like your previous adapter, just use an HDMI to DVI cable. Even if you dont go with this exact adapter, I would try one that is from a manufacturer that sells AMD cards (HIS, Sapphire, Visiontek etc..) .

Thanks for this! I think I'm going to go with the Sapphire, as I've also seen that mentioned by others who had problems with the Startech. I'm going to get the Startech packaged back up and sent back, and then get the new one.

I've just asked my boyfriend about the dvi cable and he says we have one, and that it should go in the 22" monitor. So hopefully if we use that and get the sapphire, it'll all work together peachy (I think what I get so confused about with monitors is partly all these plug/cable types and what works with what!)

Thanks again. Will reply again and/or update initial post when I have something new to report, in case you and nickbachu are interested in the outcome!

 

[snailau]

Sorry to revive this dead thread but another solution i've just found after none of these other solutions worked for me is, selecting the display settings for your monitor and changing the monitor's orientation to portrait. that forced the monitor to the native resolution for me and after all i did was swap it back to landscape and the problem was solved.