I have just bought a new monitor, and cannot get it to display at its advertised native resolution. My setup is:
- OS: Windows 10 Pro 64-bit
- Processor: AMD A10-7850K + integrated Radeon R7
- Graphics Card: AMD R7 240
- Old Monitor: BenQ GL2450HM LED TN 24 inch, native resolution 1920x1080
- New Monitor: BenQ GW2765HT LED IPS 27 inch, native resolution 2560x1440
When I connect the new monitor using a DVI cable, it works fine, but is only displaying at 1920x1080. When I connect it using an HDMI cable, it does not display a picture at all.
I forced Windows to detect and download the correct driver for the new monitor, so it is identified as "BenQ GW2765H", not "Generic Non-PnP Monitor".
The DVI cable appears to be DVI-D Dual Link according to this pin diagram, so as I understand it, there should be sufficient bandwidth to support the higher resolution.
I tried several different HDMI cables, but none of them produce an image.
I tried all of the following sockets:
- Motherboard DVI
- Motherboard HDMI
- Graphics Card DVI
- Graphics Card HDMI
I'm now thinking maybe it's not the cable, but the graphics card. Maybe a R7 240 can't output a fast enough signal? Can anyone confirm this? I have searched online, but can't find anything definitive.
The HDMI problem is bugging me more than the DVI problem at the moment, so I dug out a laptop that has an HDMI port, which I know can successfully connect to the TV. I connected it to the new monitor, still no image. OK, so it's probably the monitor.
I tried pressing the On-Screen Menu buttons at random to see if any useful options appeared. Bingo! I found a menu where you have to select the type of signal input (DP/DVI/HDMI/VGA). I set it to HDMI, and I got an image. Phew. This is the first time I have encountered a monitor that wanted you to manually select the input type. How weird.
I connected the new monitor back to the PC using the HDMI cable, and it worked straight away. I now have the old monitor connected via DVI, the new monitor connected via HDMI, and the new monitor displaying at 2560x1440 resolution.
I still don't know what's up with the DVI cable, but my problem is now solved, so I'm going to leave it there. Thanks to everyone who commented. :-)