R9 390 at 3440x1440 144 Hz

[Hypermale]

I have just bought a new 3440 x 1440 ultrawide monitor capable of 144 Hz (AOC 34CU2GX/BK) and I have hooked it up to my PC, via a display port cable, running a Radeon R9 390. Despite much trying and searching the internet, I can't seem to get windows 10 to output at 144 Hz; in windows settings I only have 60 Hz and 100 Hz options. If I lower the resolution to 2540 x 1080 then I get a 144 Hz option, but I bought the monitor to see 1440p.

I know an R9 390 card is a little older now (I am considering upgrading to a 5700 XT) and I've not yet played any games that give me >100 fps at 1440p anyway, but the fact I can't get 144 Hz is annoying. I was hoping to turn down the settings on CS:GO to get closer to 144 Hz with my R9 390. My best guess at the moment is it's a GPU driver issue (but my drivers are up-to-date). The monitor has DP 1.2/1.4 compatibility and I think (but not sure) my graphics card has a DP 1.2. Do have any thoughts on this? Is this just some fundamental limit of older GPU's? Any help is much appreciated.

 

[Hypermale]

Thanks for your reply.

That would make sense. I can get 2560x1080 (21:9) at 144 Hz (and 120 Hz), but I've not tried 2560x1440 (16:9). I guess asking a R9 390 to do 3440x1440 at 144 Hz is pushing it a bit anyway. Maybe I'll use this as justification to upgrade my GPU and get DP 1.4.

 

[Hypermale]

You could try forcing the resolution / refresh rate, worst case it doesn't work.

I considered this as there's an option for 'custom resolutions' in the Radeon software, but of course you have to tick the box acknowledging that things could go wrong, hence I was a little hesitant. I've never overclocked a GPU and I'm not sure how aggressive this is, or if even counts as overclocking. I would hope that with modern protections, if I did asked for something unreasonable it would simply say 'no' and go back to previous settings. Perhaps it's worth a shot.

100Hz should be a nice compromise until you get a better gfx card though. It's nice and smooth iirc from my old 100Hz UW days

I agree. I'm very much a casual gamer, so my performance in game is not limited by not getting 144 Hz. I was quite happy with 60 Hz on consoles until I discovered the power of PC gaming.

 

[Hypermale]

You could try forcing the resolution / refresh rate, worst case it doesn't work.

Following up on setting a custom resolution, it does not seem to work for 144 Hz. I believe it is due to the pixel clock of my R9 390 not being fast enough. The maximum it can have appears to be around 650 MHz but I'd need 783 MHz according to the Radeon software. However, I am able to get 110 Hz as the required pixel clock rate is 598 MHz. I've not checked this for stability though, but I can at least select the option in the Windows settings and the frame rate counter option built into the monitor shows 110. So good suggestion, SonicSW20. Thanks.