difference between directx7 mode and directx9 mode

I heard that some game can be played in either directx7mode or directx9 mode. What's the difference? Does directx9 mode require more powerful graphic card (not about directx9 compatibility, just difference in raw power)?

 

DirectX 9 (SM2) mode certainly looks much prettier, in theory. It offers many more features and effects that DirctX 7 ("Fixed Function" SM) can't hope to execute, especially in particle effects and transparency (water, smoke, shadowing, etc.). However, DirectX 9 mode requires much more GPU horsepower, and of course fewer GPUs support it, although any semi-modern card, GeForce FX or RADEON 9500 or better, will - albeit probably DX9 mode will not be playable unless you have at least a GeForce 6 series or ATi x100-series.

And all the prettiness in the world doesn't matter if you're getting 4 frames per second. Just experiment with what works best.

 

What is the lowest acceptable FPS in general? I am quite surprised to see people complain about <30 frame rate. Movies run at 24 FPS and nobody sees any jerkiness.

Is it possible to run Call of Duty2 in directx9 mode decently?

 

Well, we use 30 as "something to shoot for" - it is technically speaking the rate at which the eye cannot distinguish between the frames. Yes, movies run at 24, but actually if you watch action scenes in them very intently - as you would a FPS game, for example - you can see the jerkiness and/or ghosting inherent in the technology. Generally speaking, 30 is considred acceptable for FPS games, although depending on your "sluggishness tolerance level" 25 or even 20 might do fine for you. In RPGs and RTS games we obviously don't need quite such fluid action because split-second reflexes are less important. 25 or 20 is considered okay for most RPGs; 20 or even 15 is passable for RTS games.

As for your second question...well, naturally it's possible. 8800s can do it. 7900s can do it. x1900s have no problem. Heck, my overclocked Go6800 can do it fairly well most of the time. But a 6150Le or x200M hasn't got a prayer. If you'd give some stats on your system I could better answer that question.

 

This is actually more dependent on personal preference. Some gamers are more sensitive to faster FPS rates than others.

Definitely. Are you asking if it's possible on your system? It depends on the configuration of your system.

 

Movies can run at a lower FPS because the ghosting on the TV somewhat smooths out the video. If you concentrate, as posted, movies appear jerky.

For a first person shooter, you are going to want a minimum FPS of around 30, so an average around 40-45 or so. The minimum FPS is the most important, not the average. You don't want to be barely hitting 30FPS, and then all of a sudden get into a firefight and have your frames go down to the high teens - lower 20s. Keep your settings where your card can comfortably maintain a stable framerate.

 

I find anything less than 40 fps painful in CS:S, and anything less than 30 fps unplayable. In Oblivion, anything around 30 fps is OK, but anything less and you'll start to miss against the quicker monsters because of frame lag.

 

Sorry, I somehow forgot to say x1400.

The spec most likely will be ati x1400, T7200, and 2GB of RAM.

 

Dx9 mode is possible, but, I'd recommend Dx7 mode to squeeze out every available frame - the game doesn't look significantly inferior, and trust me you'll need every frame you can get when the heavy action starts to kick in. In dx7, you can at least increase the other settings fairly high as opposed to having to lower your settings in Dx9 mode.