MiSTer FPGA Forum

Does anyone with an LG OLED C9 ever get their MiSTer working in 1440p ?

Yes, try another cable

No I never got it to work on a C9 even using a 8k certified HDMI cable.

I have the B9 (which has a slower CPU, but I think it has the same scaler), and it does not support 1440p. I think they started supporting 1440p with the next generation, the CX?

2560x1440p works fine on my C9 via Retrotink or as a PC Windows resolution. But the 1920x1440p 4:3 resolution from the MiSTer isn't supported. A shame, there is no technical reason for that. The CX can do it.

If I were to take a guess, there is an actual technical reason — not developer laziness

MiSTer's current max resolution is 2048×1536 = 3,145,728 pixels, also pushing the DE-10 nano further than it is intended to go, if I remember correctly.

2560×1440 is quite a bit more bandwidth at 3,686,400 pixels.

(While 1920×1440 is 2,764,800 pixels, well below the iPad 3 resolution, which is currently the max supported one)

Actually not. The C9 and CX are technically nearly identical. Pretty much the same firmware too. LG doesn't support minor updates to slightly older models. Company policy or just plain laziness. Who knows.

1920x1440p should work on an C9, ist just a 4:3 resolution (since the 16:9 2560x1440p works fine for me). It's not limited to the MiSTER, it's just unsupported. So, no plain blackout because the WebOS tells you that (PC doesn't support 1920x1440p neither btw).

I meant MiSTer developer laziness, maybe that's where we got confused

My point was that I don't think the MiSTer has enough bandwidth to supply 2560×1440. And yes, I'm sure they could have backported that from the CX to the C9, but TV manufacturers rarely care about older models once there's a new one for sale.

There is a 2560x1440 Mister mode you can try (mode=14?). However this is achieved by horizontal pixel doubling, so in effect its more like 1280x1440, thanks to limitations of Mister's scaler as mentioned. Most of the time I think one is better off with 1920x1080 compared to that, especially on a 4K display.

Maybe. But scanlines+masks looks far better in 1440p. A native 1440p display would be perfect, but 1440p scales most CRT filter nicely on a 4K display.

1920x1440p is actually a higher clock than the de 10 nano can handle (on paper). Set dvi_mode=1 gives you some extra bandwidth that might give the extra omph needed

2560x1440 (mode14) use less bandwidth die to horizontal pixel doubling. 2560x1440 is impossible as far as I can see on a de 10

Retro-Nerd wrote: ↑Thu Aug 17, 2023 5:06 am

Maybe. But scanlines+masks looks far better in 1440p. A native 1440p display would be perfect, but 1440p scales most CRT filter nicely on a 4K display.

I'm talking about the faux-2560x1440 pixel doubling option, like you seem to be stuck with on the C9. You're getting only half the horizontal resolution on masks, never mind much less room to interpolate pixels on the horizontal axis, where you really need it to maintain OG aspect ratios. And 1080p is already 5x integer if you are comfortable with a bit of cropping. 2560x1440 is giving up quite a lot for little in return. Poorly scaling 1440p monitors that also reject 1920x1440 is the only scenario I'd even consider it for.

Pixel repitition is quite pointless for CRT filter, it looks awful. I mean 1440p generally. It looks pretty good on my Dell 27 inch monitor (native 1440p) via MiSTer. The filter effects are more authentic over 1080p (more refined). MiSTER (via analogue out)+Retrotink 5x Pro looks good too, but then in 2560x1440 (with a proper 4:3 image) on my LG C9.

I don't like the 1080p cropping anyway, there are always games where you cut something from the image.

I prefer 1920x1200 and vscale_mode=5 for my LG C9 (Mister HDMI out). You don't need cropping for 5x and most vertical Arcade games fill the screen pretty good.