This is something that has mystified me ever since sites like THG started reviewing mainstream 3D cards (back in the TNT days)... the talk was all about how many FPS a card could get. But really, why?
Let me justify my line of questioning here...
Since day 1, video cards have traditionally though of as limited by the polygon and pixel count they can push, and now how fast the CPU can push the data to the card. While these are all valid concerns when pushing raw frame rate, there is a limit here...
... and this limit is neither the video card or the CPU. It's the monitor. Be it an LCD or a CRT, the monitor is only going to display upto a certain number of frames, based on the response time or refresh rate of the monitor. Physically, a CRT cannot display any more frames per second than the vertical refresh rate allows for. Same goes in a similar fashion for LCD's response time (though this is a little different since each pixel can be managed independantly - though currently it isn't).
So what does all this mean?
This means that if your refresh rate is, say, 85Hz, the maximum FPS you will see is 85fps. Sure, now you're going to say "well turn off V-Sync". We're not talking about V-Sync here... in fact V-Sync does exactly what I recommend to do. But for all intents, right now, consider V-Sync as off. Sure, your game might be displaying 200FPS, but your monitor, regardless of what's going on inside the computer, is only going to display upto your refresh rate. Period. Any additional frames being generated are going to get sent to the frame buffer, and then overwritten with the next frame before the framebuffer is sent to the monitor on the next refresh interval. So at ~200FPS, you're actually losing 1.5 frames for every frame you output to the monitor. Wasted.
Worse yet, with a CRT's "scanning" technology, if you're pushing more frames into the framebuffer than the CRT can display per refresh, there is a very distinct possibility that you're going to display part of frame A during the top half (or portion) of a scan and the frame gets rewritten before the refresh is over, causing part of frame B to be displayed. Oh hey! That's what's called "Tearing".
So what do we do now? V-Sync locks the display driver to literally stall the next frame until the screen refresh is done before the next frame is sent to the framebuffer. All is well. There are a few other things that help with IQ and such, but that's not what I'm discussing.
My point is that 200FPS (or whatever) is all fine and good, just like any sort of ego-stroking. But it does you no good. It does more harm than good. You're pushing framerates too high for no reason, and in fact, it's going to cause other things to suffer. If you're not wasting the CPU horsepower on the additional frames you never see, you can use it for things like better sound, better physics, better IQ and god forbid better AI.
The only saving grace in the future will be pure digital displays where each pixel on the display is hooked directly to a "pixel" in the framebuffer, independent of any refresh or scan rate. This will be a fundamental change in display technology, allowing for nearly infinite framerates to be displayed without penalty as each pixel can change independently at any time to any color. Of course this technology will not be happening any time soon...
Cliff's
Since everyone likes analogies, it's like an 1.8L inline 4 in the Senta versus a 6.0L V-12 Viper... Sure the V-12 can push out a lot more at the high end, but in the end, the speed limit on the highway is only 65MPH.
Let me justify my line of questioning here...
Since day 1, video cards have traditionally though of as limited by the polygon and pixel count they can push, and now how fast the CPU can push the data to the card. While these are all valid concerns when pushing raw frame rate, there is a limit here...
... and this limit is neither the video card or the CPU. It's the monitor. Be it an LCD or a CRT, the monitor is only going to display upto a certain number of frames, based on the response time or refresh rate of the monitor. Physically, a CRT cannot display any more frames per second than the vertical refresh rate allows for. Same goes in a similar fashion for LCD's response time (though this is a little different since each pixel can be managed independantly - though currently it isn't).
So what does all this mean?
This means that if your refresh rate is, say, 85Hz, the maximum FPS you will see is 85fps. Sure, now you're going to say "well turn off V-Sync". We're not talking about V-Sync here... in fact V-Sync does exactly what I recommend to do. But for all intents, right now, consider V-Sync as off. Sure, your game might be displaying 200FPS, but your monitor, regardless of what's going on inside the computer, is only going to display upto your refresh rate. Period. Any additional frames being generated are going to get sent to the frame buffer, and then overwritten with the next frame before the framebuffer is sent to the monitor on the next refresh interval. So at ~200FPS, you're actually losing 1.5 frames for every frame you output to the monitor. Wasted.
Worse yet, with a CRT's "scanning" technology, if you're pushing more frames into the framebuffer than the CRT can display per refresh, there is a very distinct possibility that you're going to display part of frame A during the top half (or portion) of a scan and the frame gets rewritten before the refresh is over, causing part of frame B to be displayed. Oh hey! That's what's called "Tearing".
So what do we do now? V-Sync locks the display driver to literally stall the next frame until the screen refresh is done before the next frame is sent to the framebuffer. All is well. There are a few other things that help with IQ and such, but that's not what I'm discussing.
My point is that 200FPS (or whatever) is all fine and good, just like any sort of ego-stroking. But it does you no good. It does more harm than good. You're pushing framerates too high for no reason, and in fact, it's going to cause other things to suffer. If you're not wasting the CPU horsepower on the additional frames you never see, you can use it for things like better sound, better physics, better IQ and god forbid better AI.
The only saving grace in the future will be pure digital displays where each pixel on the display is hooked directly to a "pixel" in the framebuffer, independent of any refresh or scan rate. This will be a fundamental change in display technology, allowing for nearly infinite framerates to be displayed without penalty as each pixel can change independently at any time to any color. Of course this technology will not be happening any time soon...
Cliff's
Since everyone likes analogies, it's like an 1.8L inline 4 in the Senta versus a 6.0L V-12 Viper... Sure the V-12 can push out a lot more at the high end, but in the end, the speed limit on the highway is only 65MPH.
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