Originally posted by karsonOne question though: I thought the 006 was natively a 60Hz 1080p display, not a 30Hz display? If it's 60Hz, I can get decent 60fps gaming performance using a 60Hz 1080i output from the HTPC and using the 006's internal de-interlacer to fill in the missing lines, but if it's a 30Hz display I may be reduced to playing chess online or something!
Um, here's the deal. 30Hz is plenty fast for any fast-action game. Otherwise you'd never have played any game on any television set, ever. The human eye and brain start to perceive a rapid slide-show as actual motion at about 24Hz, which is why movies (and PAL television at 25Hz) use that rate. NTSC uses 30Hz because it's a little faster than 24 and syncs up nicely with our 60Hz power grid.
When you see game benchmarks that claim "164 frames per second", it's just a convenient way of measuring how fast your computer (CPU and video card, mainly) is over the life of the benchmark. Most games will never
display more than 30-40 frames per second because that's how fast the game engine operates.
Every game engine is a little different, but id Software's family of Doom and Quake game engines makes a good teaching example. They all have a mode called "timedemo" that very few people actually know what it does. The original Doom engine is the simplist example: during normal gameplay the engine divides all timing and events into a 35Hz system. (Newer engines do use a faster base clock, I just happen to recall that Doom used 35Hz.) If your computer is capable of more than 35Hz, you get 35Hz, period. If your computer is not capable of 35Hz, you get what it is capable of. If your computer is capable of more than twice that, you'll effectively get multiple frames that are exactly the same--but the picture can only change 35 times per second because nothing in the game moves more often than that. (All of this is further limited by the refresh rate of your monitor, but that's another topic.)
The timedemo mode turns this notion on it's head. Instead of connecting the game engine to a real-time clock so that time in the game passes, well, in real-time, the game engine is set to run as fast as the display will allow with the assumption that each formerly-35Hz tick of the clock gets rendered exactly once, regardless of whether your computer can do it faster or slower than that. Then you can calculate the speed of your system based on the number of frames it renders (variable in normal gameplay, fixed in timedemo) versus the time that elapses from start to finish (fixed in normal gameplay, variable in timedemo).
Number of frames versus elapsed time? Frames per second. But no one plays the game in this mode.
It's just a benchmark. You might as well try saying that a Porsche going 55mph is "faster" than a Yugo going 55mph. Not really true. What is true is that the Porsche's extra horsepower makes it more likely to still be able to sustain 55mph up a steep hill.
So can we please stop with the complaints that "30Hz isn't fast enough for games" since I doubt that anyone saying it has ever actually played a game at 120Hz--even when they think they have.
Over-simplified short version for Penton-Man
, who admits to skipping over long posts no matter how brilliant and/or insightful they are:
All games run at 30Hz.