- A Lenovo Z500 laptop with:
- GPU: NVIDIA GT635M 1GB & Intel HD4000 (this is an Optimus laptop, so I use the NVIDIA for both -- note that both struggle with the 4000, but FG just falls on its feet while TF2 is still usable)
- CPU: Intel® Core™ i5-3230M CPU @ 2.60GHz (dual core but with hyperthreading so technically quad)
- 4GB of RAM
- 1TB HDD (I am not sure of its speed, I think its only 5400RPM. 606GB is dished out to Ubuntu)
I have also tested FlightGear on Windows 7, but I have not managed to get a comparison and having everything else on DirectX blurs the line slightly. Nevertheless, FG still performs badly (best frame rate on max settings is 15 FPS).
My FG settings are max on all shaders, multithreading on DrawThreadPerContext, all graphics settings enabled excluding Random buildings and tree shadows. Clouds were on 0.64 density and ~110000m visibility with detailed weather enabled. Multiplayer was turned off. Airport was KSFO 28R with ufo. The weather report is posted below, as the conditions will have a load on what is being rendered and how things perform.
Let's take a look at what FPS and spacing we get in game. From the horizon:
A miserable 5 frames per second. Makes FlightGear a pain in the ass to use.
Now lets look at the FPS while we look at the ground:
As you can see, 20/21 frames per second. Okay-ish.
The performance looking at the sky:
24/25 fps.
Now lets take a look at load factors on my machine.
FlightGear within that scenario is using little of the GPU. This is something I do not get about FlightGear and why it is so slow, as Team Fortress 2 will use 92% of VRAM and have a much higher GPU utilisation but will always run at 59/60 FPS with good frame spacing rates.
CPU and RAM:
Team Fortress 2 will use the same amount of CPU and even more RAM. But it will still run faster with everything on highest settings (excl. anti-aliasing and anisotropic filter which are both on 4x).
I should make a note -- I have noticed with multithreading, that FG will decide to max out one core (typically core 3) instead of sharing it around.
Conclusion
Now, I understand that this is a very distant thing in comparison to Team Fortress 2. But the numbers win in a situation like this and as you can see, FlightGear just isn't good enough. It is poorly optimised and I leave it permanently responsible for damaging my computer's performance. If I didn't take apart my laptop and blow compressed air into the fan to get rid of the dust that has collected, I would not be able to run things like Team Fortress 2, the game would just degrade in performance.
This was also the case with my old laptop, which FG also destroyed until I did the same thing as above. FG would run really really slow, on a quad-core i7 with a NVIDIA 540M @ 2GB. Team Fortress 2 and just about every other game that I played? Well, I never got anything lower than 40 FPS on both machines. The big difference, I believe, is that the Source engine appears to pre-load just about everything. TF2 is notable on my machine for bottlenecking badly when loading a game.
Changing FG's graphical settings does little or nothing. If I switch all the shaders to zero, I get no performance boost. If I turn off ALS, I get no performance boost. If I turn off detailed weather, I get no performance boost. I don't think I have to repeat this any more. So, to prevent my computer from permanent damage, I will not be using FG any more.