Is SLI a good way of getting increased frame rates in FSX?

[LUFTY]

Paul,

SLI is a function of the graphics driver. It is not the case that FSX 'does not support SLI'. Most peoples performance is however limited by the processor. If your processor can keep the graphics cards busy then you will see increased performance with a SLI configuration. Since SP1 FSX has been able to utilise multiple threads and take advantage of multi cores (mainly texture handling).

Regards,
Will

Hi Will totally agree that the number one bottleneck for FSX is the processor speed and number of cores.

One other point to add is that DX10 offloads some of the processor overhead onto the graphics cards so a faster graphics card and running DX10 can reduce the processor overhead.

I am getting really good results with the ATI HD3870X2 because of this and am anticipating even better results with the soon to be released ATI HD4870X2 which is two HD4870 cards joined together in one card via Crossfire (which is the ATI version of SLI).

The other important bottleneck is the speed of the graphics card bus with PCI Express 2.0 allowing a much bigger throughput than PCI Express 1.1.

With high resolutions and complexity FSX will max out on data being passed over the PCI Express bus.

Kind regards


Lufty

[Denis]

Hi,

FS9 and FSX cannot use multi GPU. They can work on such setup (SLI, Triple SLI or Dual GPU Card). But Each graphic cards benchmark (like these from Toms'hardware) can demonstrate that e.g. a 9800 and a 9800GX2 have same results in FS. This is true for every GPU generation, Nvidia or ATI.

And this is true for every resolution ! you can see this on a 800X600 15" screen or a Triplehead2Go with trhee time 1680X1050 22" widescreens ! Multi GPU has no effect !

The last weeks, we saw that FSX has paradoxal results with hardware, the last Nvidia GTX200 cards are slower then the 2 years old 8800GTX. A month later, new drivers gave same fps, but not better then a 8800GTX. The same GTX200 outperformed very well each other single GPU card in other games. So it is...

If you want invest better, buy a single PCI-Express 2.0 compliant GPU (and motherboard) card and use the saved money with a faster CPU, a good CPU cooler, and overclock your CPU. And then you will feel the difference !

Best regards

Denis

[LUFTY]

Hi,

FS9 and FSX cannot use multi GPU. They can work on such setup (SLI, Triple SLI or Dual GPU Card). But Each graphic cards benchmark (like these from Toms'hardware) can demonstrate that e.g. a 9800 and a 9800GX2 have same results in FS. This is true for every GPU generation, Nvidia or ATI.

And this is true for every resolution ! you can see this on a 800X600 15" screen or a Triplehead2Go with trhee time 1680X1050 22" widescreens ! Multi GPU has no effect !

The last weeks, we saw that FSX has paradoxal results with hardware, the last Nvidia GTX200 cards are slower then the 2 years old 8800GTX. A month later, new drivers gave same fps, but not better then a 8800GTX. The same GTX200 outperformed very well each other single GPU card in other games. So it is...

If you want invest better, buy a single PCI-Express 2.0 compliant GPU (and motherboard) card and use the saved money with a faster CPU, a good CPU cooler, and overclock your CPU. And then you will feel the difference !

Best regards

Denis

Hi Denis

I agree PCIe 2.0 does make a difference to framerates whereas dual cards has little if any affect.

The latest performance benchmarks from Tomshardware highlight this although they used a relatively slow CPU which is by far and away the biggest bottleneck with FSX.

http://www.tomshardware.com/reviews/...n,2007-18.html

Regards


Lufty

[strychninekiss]

Hi all.

Yes, frame rates in FSX is definitely based on the CPU like Denis said!
I currently have a core 2 duo E6850 3.0GHz I get around 8-15 FPS with high settings, I am sure if I clock my CPU up a bit I can manage around 10-20 FPS.

However I have never overclocked a CPU and Im kind of nervous! =)

//William

[AchillesP]

Biggest problem Paul, is 100% For sure FS9 will not utilize the second processor, so no point really!

Hi,

There is a trick to activate all cores for fs9.

1.) run fs9
2.) open the program scheduler and find fs9.exe
3.) right click and properties. Check all procesors.

You have to do this every time you run fs9.

[Padraig]

Hi,

There is a trick to activate all cores for fs9.

1.) run fs9
2.) open the program scheduler and find fs9.exe
3.) right click and properties. Check all procesors.

You have to do this every time you run fs9.

You can create batch file with notepad and use the command for setting the affinity for the fs9.exe.

Launch the Fs9.bat file every time you want to use FS2004, make sure to use the START command at the start of the line so the CMD window will close after the exe is launched.

Google "Batch file set affinity for exe" and you`ll get some examples.

I am not sure if setting the infinity is going to give you better performance tho. Just thought I give you tip without having to do the infinity thing every time you start fs9.exe manually.

[LUFTY]

Hi,

There is a trick to activate all cores for fs9.

1.) run fs9
2.) open the program scheduler and find fs9.exe
3.) right click and properties. Check all procesors.

You have to do this every time you run fs9.

Hi Achilles

This will tell Windows to allow all processors to be used for FS9 however it will not make any performance difference as FS9 is not multithreaded which means in simple terms that the whole application runs as one processing thread. Therefore whenever FS9 wants to do some CPU processing it can only send the requests to the CPU one at a time rather than sending parallel requests to seperate cores.

In fact this is not the best way of optimising FS9. A better way would be to use the affinity option to make say core 0 run all windows tasks etc. and set the affinity of FS9 to the second core.

Regards


Lufty