Optimus laptop; proper settings ? (chipset not compatible, unstable games)

[schmerzkaufen]

Hello everyone!

I often use GM on my everyday laptop (which uses nVidia Optimus technology) and things have been great but not entirely, there are two issues;

1. I always get the 'video chipset not compatible' warning, although I've specified my system to use the nVidia 820m chip for the MAME exe, it seems it still has to go through the Intel iGPU for some reason. Not sure how it really works.

2. Some off-60Hz games like for instance Darius Gaiden @58.97Hz don't stay smooth (random sync drops/hiccups) even with -autosync on and sync_tolerance @2.5

Is it my computer's Optimus architecture that's creating problems or did I mess up the ini settings? Not sure I understand how lcd-range works, nor how to properly set up GM for a basic LCD configuration in general. Maybe I expect too much from it since it is limited to 59-61?

 

log and mame.ini attached, using 0.182 but the issues are the same with older and newer builds.

[pakoman]

On windows you simply need ATI/AMD chipset.

[schmerzkaufen]

Er, no...not for my use.

[schmerzkaufen]

Bump ? 

[Calamity]

Hi,

The 'video chipset not compatible' message is normal, it's just telling you GM won't be able to program the video card for custom video modes, that's all.

I'm testing dariusg here with v0.189 and it seems to run smooth. I'm using an LCD with -sync_tolerance 2.5, the speed goes up to 102% as expected and I can't notice anything wrong.

My laptop also uses the Optimus architecture, it was a big disappointment when I realized how it works. Even if you select the Nvidia gpu for a certain program, the low level stuff (video modes) is still handled by the Intel chipset. However I can't see how it could be causing the issues you describe.

The lcd_range setting has nothing to do with this, it was meant for Powerstrip + LCD use.

[schmerzkaufen]

Thanks a lot Calamity, BTW I forgot to mention that when the framerate drops happen sound is distorted as well (as expected)

with that I went and checked a number of things;

- tried an older GM build (0.170) up to newer (0.188) > same result
- reverted from portaudio latency 1, to auto latency 2.0 > same result
- suspecting Win Defender (btw im on Win 8.1) I installed Avast > same result
- made sure no buffering is forced on GM in the nVidia control panel, leaving it controlled by application > same result

That's really strange, I'll investigate further and try several other off-60Hz hardwares and see if I notice something.
I don't know if my memory's wrong but I thought I remembered that some time ago every game falling under my defined sync_tolerance ran butter smooth on that very same laptop.
Arf, mystery.