Confirm my monitor's failed?

pendulum

Hi.

I have a dual screen setup with a 24" Viewsonic Optiquest Q241wb, which I use as my main monitor, and a smaller 19" BenQ.

I turned the PC on today, and as usual it passed the POST check, and the Windows 7 loading screen came up normally. However, as soon as the Windows login screen came up, the picture on my main monitor started constantly jumping and flickering all over the place and the colours were wrong. The other monitor was fine.

I rebooted, but the same thing happened.

I suspected a loose cable, so I unplugged the power and video cables and reattached them, but still the same thing happened.

As the video output is absolutely fine until the point when the Windows login screen comes up (and beyond), I suspected it may be drivers, especially as I had upgraded within the last week to the latest nVidia drivers. So I tried different driver versions. Still the same.

I then tried booting in to XP, which I haven't done in months, and it was still the same. The POST displays fine, the XP loading screen displays fine, and then it goes crazy as soon as the Windows login screen comes up.

Somewhere during this process, I began fiddling with the Display properties, and I seem to have discovered that selecting a much lower resolution 'fixes' the problem. The monitor only misbehaves when in a high resolution including its native resolution. 800x600 is fine. That would explain why POST and the Windows loading screen display fine.

I didn't know if this was down to the graphics card or monitor, so I dragged an old PC out of retirement and hooked the monitor up to that (using a known good video cable).

The same thing happened, so to my mind that rules out my system being to blame, or software. It must be the monitor to blame or its settings. I tried to "Reset" the monitor but it made no difference, and the settings seem fine.

I haven't tried a new power cable. I'll try that after I've had some sleep. But I can't see it being that really.

So my question is along the lines of:

What would cause a monitor to go mad at a higher resolution but be fine at a lower one? Can I fix this or is it fatal?

If you have any other comments that may help me to save this monitor I'd also like to hear them

Thanks for reading!

OneADay

If your graphic card is capable of high resolutions but your monitor isn't, then it would cause some of the problems you indicate. Try safe mode boot - and test different resolutions to see what the highest one you can get working?

Hammyman

Windows is setting the incorrect refresh rate for the monitor. Either that or there's a physical fault with the card. Swap the VGA/DVI/HDMI cable from the smaller monitor to the larger. If the larger then plays up, its possibly the card.

pendulum

Thanks for the replies.

I have swapped the video cables over and also introduced a known good cable. The smaller monitor worked fine with the cable from the main (faulty) monitor.

I don't think it's a physical fault with the video card because I plugged the monitor in to a completely different computer system, with a totally different video card, and the same thing happened.

I've looked at the refresh rates as suggested and fiddled with the resolutions.

800 X 600, True Colour, 60htz = OK
1024 x 768, True Colour, 60htz = OK
1280 x 720, True Colour, 60htz = OK
1280 x 800, True Colour, 60htz = OK
1280 x 1024, True Colour, 60htz = OK
1360 x 768, True Colour, 60htz = OK
1600 x 900, True Colour, 60htz = Started to go funny. Pixels take the wrong colour and there's some jerkiness. However, after ten minutes when I tried it again, it was fine. Better when warm?
1920 x 1080, True Colour, 60htz = It's all over the place. Can hardly see anything on the screen.
1920 x 1200, True Colour, 60htz = It's just as bad.

I sat with it at 1024 x 768 whilst I wrote this post and did other things. I then went to try it again and set it to 1920 x 1200 and it worked fine! Better when warm again...

I turned the monitor off at the button and on again and it was still fine.

Still at 1920 x 1200, I unplugged the monitor from the mains and left it for half an hour:
When I came back, it was a black screen at first, then it had jumping lines and flicker, and was all over the place (picture unreadable). I slowly watched it get better and better and after 2 or 3 minutes I am now able to write this post (at 1920 x 1200) and the monitor is fine.

Has to be a faulty monitor? It seems like it struggles to output higher resolutions until it is warmed up. I wonder if its fixable?

OneADay

Doubt fixing it would be cheap.
You could go all the way back and unistall all the drivers completely and start with graphic card drivers and the monitor drivers (which that model apparently has some according to the viewsonic web site).

Check the graphic card configuration (if it has some settings) or try another OS (drastic). If its under warranty, contact Viewsonic or just contact them anyway, might point you in the right direction.