OBS can't "see" some boot menus or Hirens

[ScottMerrill]

I've used OBS extensively and have no issues with standard screen capture, and often times, I can record computer boot screens with no issues. I have been wrestling with how to get it to recognize a bootable OS like Hirens Boot CD (or similar). I'm sure it's a driver issue somewhere, just can't seem to find anything on it. This is specifically with Hirens (or Medicat, Linux, etc).

I've got a decent but cheapo HMDI capture card that works for everything else. Video card is NVidia GeForce RTX 2060 (updated). Any suggestions? Bugging the crap out of me that I can't screen record my Hirens stuff.

Thanks in advance!
Scott

 

[koala]

With "[can't] record computer boot screens", you mean you capture some computer via hdmi with a hdmi capture device connected to a computer that is running OBS, and try to record the boot process of the captured computer?

It may be the bios or the bootstrap software (from boot cd) of the booting computer is switching to some video mode your capture device doesn't support. May be some unsupported resolution, may be some unsupported text mode, may be some unsupported fps rate. May be it's unsupported because it's some extremely basic video mode nobody uses for daily usage but only in boot screens, so it's not built in the capture device.
If this is the case, it's not an issue with the computer running OBS, it's an issue between the captured computer and the capture device.

May be it's possible to explicitly set some video resolution/fps for the capture device in the properties of your "video capture device" source in OBS to override some failing auto-detect within the capture device.

 

[ScottMerrill]

I figured it had more to do with the video mode being output from the source computer once the USB bootloader takes over. Just odd that it sometimes will work with a Dell or HP boot screen, but not a very basic utility like Hirens, which uses a basic VGA driver. I've changed all the video settings for the source to the lowest they will go, thinking that might be it, no go. I just get the colored vertical bars and that's it. Every other function in OBS works perfectly.

Not the end of the world, as I can load Hirens in a VM session for most things, but I'd love to be able to actually connect to a client computer that I'm actually working on, to demonstrate the fixes in real-time.

Thanks for your help, regardless :)

 

[koala]

Some boot cd's allow explicit setting of some non default/different vga mode. May be that other mode can be captured by the capture device.