480p Output from PC to PVM-14L5

[DuxPrime]

I recently acquired a PVM-14L5 for the purposes of using it as a desktop gaming monitor connected to my PC. My video chain is an Arcade 5000 GPU (effectively a Radeon HD 5450) → Extron RGB 109xi to combine sync → PVM-14L5. I'm using CRTEmudriver to create the various resolutions the monitor supports.

At 240p, the monitor looks great. However, when switching to 480p, the image becomes much darker and what seems like shadows from darker screen elements appear. I created an album showing how the images appear using Sonic Mania running in 4:3 mode. The shadowing is most noticeable on the pause screen.

As a sanity check, I tested the 480p mode with RGB output from my Dreamcast (via Hanzo VGA box) and it appears as I would expect.

Does anyone know why my image looks off when using 640x480 from my PC?

[Dochartaigh]

Try adjusting CLP P DLY in the service menu. Not quite as striking as my video below, but that might be the fix. Write down your default value beforehand of course.

https://www.youtube.com/watch?v=DRAb9N1jgSM

[BazookaBen]

You know CRT Emudriver already supports composite sync, you don't need the Extron

[DuxPrime]

You know CRT Emudriver already supports composite sync, you don't need the Extron

Thanks for the reply, but that's not really what the thread is about. This isn't the first time I've posted here where your comment didn't contribute to the conversation and just served to try and dunk on me. Engage in good faith or don't engage at all.

[BazookaBen]

You know CRT Emudriver already supports composite sync, you don't need the Extron

Thanks for the reply, but that's not really what the thread is about. This isn't the first time I've posted here where your comment didn't contribute to the conversation and just served to try and dunk on me. Engage in good faith or don't engage at all.

That was a dunk? It was just a statement. Don't be weird

And I didn't really have good answer to your 480p issue, though now that I think about it, it could be that the horizontal porches are too small. I've seen that cause darkness on my PC CRT before.