Poor Performance with Nvidia Optimus GPU in Linux

[PoppinC]

Hi everyone,

I have an Acer Aspire V3-571G (intel i5 3210m, 8GB RAM) laptop, running Ubuntu GNOME 14.04, with both integrated graphics (Intel HD 3000) and a dedicated "optimus" GPU (Nvidia GT630M) which is only used when necessary. On Ubuntu, with the latest nvidia graphics drivers, using the dedicated GPU requires actively switching it on in the nvidia-settings program, before logging out and back in again. When playing KSP, I have always used the dedicated GPU, and experienced a small amount of lag, especially when flying near Kerbin's surface. I always thought this was normal for my laptop!

Last night however, I forgot to switch on the GPU, and accidentally started up KSP with the integrated graphics chip. Whilst the game didn't look great (no in-game anti-aliasing for linux, I usually force it with the nvidia driver) it ran incredibly smoothly, with a much higher frame rate that I've ever had with the GPU (even with all settings, AA, anisotropic filtering etc. turned to a minimum)!

Does anybody know of any reason why my dedicated GPU could be performing much worse than the measly intel integrated graphics? Surely the performance should be way higher with the Nvidia chip?

Thanks in advance for any help

C

[Gue__1]

Your gtx630m should indeed be way faster but..... I see you use a laptop and on laptop the GPU get's turned down when being on battery.

I think the intel 3000 is going full power and your gtx630m not. try putting it on power to see an effect.

If that's not it then i guess it's just the driver.

Gue

[PoppinC]

No, it's not that, my laptop is almost always plugged in, thanks for the suggestion though