When you connect three, you said Windows knows there are 3 monitors? In Windows>display you actually see three monitors listed? If yes they should be labeled 1,2,3 inside display. You can try “project to this monitor“ inside display to the monitor that stays blank.
Oh.... no that doesn't work either. Have tried it numerous times and when I do that, they all blink, it displays on the black one, but one of the other ones goes black and becomes inactive. I can do that back and forth, but it will not allow for all three to be active and display at the same time.
I can not think of a way to fix this issue now but since you said it used to work for 3 VGA monitors and it does not any more now, perhaps do a clean install of Windows will return you to the point of working w 3 VGA monitors again.
Your cpu i7-3770 has intel HD Graphics 4000 which supports up to 3 monitors. https://ark.intel.com/content/www/us/en/ark/products/65719/intel-core-i7-3770-processor-8m-cache-up-to-3-90-ghz.html the max resolution of HD 4000 is supposed to 2560×1600 through DisplayPort. First try connect two of your existing monitors to the two DP port and verify the actual max resolution you can get on them. Do they add up to be 2560x1600, i.e., each 1280x800, or more than that? I think mixing up the DP and VGA ports while splitting the max resolution bandwidth of your iGPU among three monitors may have caused your issue.
The DVI monitors have a max resolution of 1920x1200 and that is what both that are displaying are at so the combined would be more than what you listed below. I thought the max was per monitor not a total for all you are using. And that still doesn't explain why the original three VGA's won't display together as they are all smaller and a lower resolution each. Are you thinking the would have some how damaged something? If so, what would that be the graphics card and would it have to be replaced?
Re: I thought the max was per monitor not a total for all
I do not think so if multiple monitors are in extended display mode. basically video card has to project a large desktop. If you cloned the desktop display then it is a different story.
I do not know why VGA used to work but now stopped. But I do not think it would damage your video card.
For future multiple monitor project it would help to estimate the expected combined resolution that can be supported by your iGPU or video card. For now, you may try lower each monitor display resolution to minimal (e.g., 640x480), and see if that helps extend over more than 2 monitors.
I'll give it a try along with the other suggestions and those of another person to see what happens. Hopefully something will work. If all else fails I have a USB to DVI-I adapter/external video card and DvI-I cable ordered that is supposed to support up to 1920x1200 resolution so I would think that would solve the issue.
GW20
8 Posts
0
May 10th, 2020 10:00
Yes, they are labeled as 1,2,3. Where in Display do I find "project to this monitor"? I am not finding that as an option.
redxps630
9 Legend
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15.4K Posts
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May 10th, 2020 10:00
When you connect three, you said Windows knows there are 3 monitors? In Windows>display you actually see three monitors listed? If yes they should be labeled 1,2,3 inside display. You can try “project to this monitor“ inside display to the monitor that stays blank.
redxps630
9 Legend
•
15.4K Posts
0
May 10th, 2020 11:00
Display>Multiple Displays>Extend these displays
GW20
8 Posts
0
May 10th, 2020 18:00
Oh.... no that doesn't work either. Have tried it numerous times and when I do that, they all blink, it displays on the black one, but one of the other ones goes black and becomes inactive. I can do that back and forth, but it will not allow for all three to be active and display at the same time.
redxps630
9 Legend
•
15.4K Posts
0
May 10th, 2020 19:00
I can not think of a way to fix this issue now but since you said it used to work for 3 VGA monitors and it does not any more now, perhaps do a clean install of Windows will return you to the point of working w 3 VGA monitors again.
GW20
8 Posts
0
May 11th, 2020 18:00
Ok, thanks for your input.
I'm actually debating just getting two 27" or larger monitors and just use two. Probably should have went that route to begin with. Live and learn.
redxps630
9 Legend
•
15.4K Posts
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May 11th, 2020 21:00
Your cpu i7-3770 has intel HD Graphics 4000 which supports up to 3 monitors. https://ark.intel.com/content/www/us/en/ark/products/65719/intel-core-i7-3770-processor-8m-cache-up-to-3-90-ghz.html
the max resolution of HD 4000 is supposed to 2560×1600 through DisplayPort. First try connect two of your existing monitors to the two DP port and verify the actual max resolution you can get on them. Do they add up to be 2560x1600, i.e., each 1280x800, or more than that? I think mixing up the DP and VGA ports while splitting the max resolution bandwidth of your iGPU among three monitors may have caused your issue.
GW20
8 Posts
0
May 13th, 2020 16:00
The DVI monitors have a max resolution of 1920x1200 and that is what both that are displaying are at so the combined would be more than what you listed below. I thought the max was per monitor not a total for all you are using. And that still doesn't explain why the original three VGA's won't display together as they are all smaller and a lower resolution each. Are you thinking the would have some how damaged something? If so, what would that be the graphics card and would it have to be replaced?
redxps630
9 Legend
•
15.4K Posts
0
May 13th, 2020 17:00
Re: I thought the max was per monitor not a total for all
I do not think so if multiple monitors are in extended display mode. basically video card has to project a large desktop. If you cloned the desktop display then it is a different story.
I do not know why VGA used to work but now stopped. But I do not think it would damage your video card.
For future multiple monitor project it would help to estimate the expected combined resolution that can be supported by your iGPU or video card. For now, you may try lower each monitor display resolution to minimal (e.g., 640x480), and see if that helps extend over more than 2 monitors.
GW20
8 Posts
0
May 14th, 2020 17:00
I'll give it a try along with the other suggestions and those of another person to see what happens. Hopefully something will work. If all else fails I have a USB to DVI-I adapter/external video card and DvI-I cable ordered that is supposed to support up to 1920x1200 resolution so I would think that would solve the issue.