Graphic card speed question

[tiburon]

What influence does the GPU speed have on FSX ?
I would like to buy a GTX 560 TI and they come in speeds ranging from about 800 MHz to 950 MHz.
Is it worth it going for the highest speed ?

Thanks in advance.

Martin

[Neil Hewitt]

This is quite a contentious issue, so expect to see multiple and differing opinions on it, but in a nutshell - FSX benefits far more from CPU power than it does from GPU power, because the GPU is used only for the rendering stage. If you have the CPU power to max out your settings, then more GPU is good for more eye-candy (you can up the AA level, turn on all the light bloom goodness etc). And if you have some add-ons like REX then again, more GPU is a good thing; but beyond the point at which FSX saturates the CPU, it won't matter how much GPU you have available. With a good, fast, modern GPU you should be able to run FSX in DirectX 10 Preview mode without seeing too much performance degradation.

It's not worth spending the extra on the higher-speed 560s, at least in my opinion. I doubt you'd gain much in the way of framerate by doing so. If you're planning on using your system for other gaming, then yes, go for the fastest card you can afford. Modern games, by and large, eat GPU for breakfast.

Consider spending your money on a Core i7 2600K + motherboard combo, invest in a serious water-cooling system, and clock it up to 5GHz+. That's the single best upgrade you can give FSX these days. You can get a reliable 4.8GHz with the 2600K, even air-cooled. Paired with a good motherboard, it's an absolute monster.

Now, should you be interesting in moving to Prepar3d in future, I gather there's work going on there to offload much of the scene calculation work to the GPU in time for v2.0 (which I suspect is still many months away yet). That will make full use of top-end GPUs and maybe then we'll all start buying ultra-expensive graphics cards again :-)

Hope that helps... perhaps a couple of the resident tweaking experts will show up and talk you through the specifics of picking the ideal GPU for FSX. It seems to be a bit of a dark art.

[tiburon]

Thanks for your very informative reply. I think my system is up to scratch : Core i5 2500k with Gigabyte P67 motherboard, 8 Gb 1833 MHz memory. I mainly fly the PMDG NGX so I'm not really considering moving to Prepar3d.
So I think I'll go for the 900 MHz.

[Neil Hewitt]

Yes, that's a nice system indeed. Out of interest, how high have you been able to clock the 2500K? The generally received opinion seems to be that it's just as flexible as the 2600K with only a small performance difference. IIRC the i5 doesn't have hyperthreading support? Not that this matters for FSX :-)

Thus far PMDG seem to be blowing cold on P3D - I read on AVSIM that they say Lockheed Martin has basically blanked them when they tried to get in touch. That contrasts with the experience of Orbx who say that LM was all over them right from the start, and as a result they're porting most of their stuff over the next few months. So you could always hold out hope for PMDG on P3D if they have a change of heart. I have a feeling that P3D 2.0 will, in many ways, be the sim that we all wanted Flight to be, in terms of performance at least.

[tiburon]

I've only had it about a month so I haven't tried overclocking it yet. I should be able to get 5 GHz, at the moment my temperature is a steady 35 C. :-)
I agree, Flight seems doomed to be a disappointment. P3d is starting to sound better and better, especially when ORBX is getting in on the act.