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fubarduck's HDTV / Video Game Lag FAQ version 2.5 Introduction First of all, keep in mind that this is not a FAQ about HDTV. If you do not understand the basics about HDTV, this FAQ may be hard to understand so I would recommend checking out an HDTV-related FAQ first. Once you're comfortable with that, read this FAQ and you ought to understand quite well how to prevent or correct any lag-related problems. Also, while much of what I post has been tested and confirmed personally, some of my information only comes from what I have only heard from owners of other HDTVs. As such, I will constantly be updating this FAQ as new information surfaces. Part I Why do HDTVs lag on video games? HDTVs typically only have one or two "native" resolutions. A set's native resolution is the resolution that it displays on the screen. This means that sometimes, the HDTV must "scale" the resolution you input in order to display it. On regular, non-HD televisions, there is only one native resolution, which is 480i (240p). Whenever you play a video game on a standard definition TV, the game console always outputs 480i/240p and the TV displays it as 480i/240p. No need for any scaling, so response time is always normal and accurate. However, because HDTVs NEVER have 480i/240p (Standard Definition) and usually not even 480p (Enhanced Definition) as a native resolution, that means that any video game console we have that can't output a High Definition signal is likely to lag on any HDTV display. It isn't that it is impossible to scale an image with no lag; HDTVs simply put the emphasis on image quality, which takes some time to process, rather than speed. Some newer HDTVs now come equipped with a "Game Mode" to speed up the scaling process and reduce or eliminate lag on the set. You can read more about "Game Mode" later into the FAQ. So just how bad is the lag? Although there is no real way to measure, and the numbers vary based on the HDTV, the average HDTV seems to lag roughly 6 frames, or 1/10th of a second when processing 480i material. DLP HDTVs seem to be a bit worse, some people claiming lag up to 15 frames, or 1/4th of a second. If these numbers will not affect your gaming habit, don't worry about it too much. Casual gamers probably will not notice a lag this small; you can stop reading and get back to gaming if that's the case. The most affected gamers will be those who play ultra-time sensitive games such rhythm games, sports games with swinging/kicking meters, shooters, or fighting games. If you fall into one of these categories, please read on. UPDATE: There IS a way to measure HDTV Gaming Lag now. Guitar Hero II for PS2 and X360 has a built-in test under the video options, which measures lag in milliseconds. (~17ms = 1 frame) I also recommend checking out this page started by another helpful AVS Forum member: http://hdtvlag.googlepages.com/ Here, you can actually see someone who measured the problem very accurately with LCD HDTVs. The test on this site was done with 480i material. Will my HDTV be affected by video game lag? The greatest problem of video gaming lag occurs when playing 480i/240p (Standard Definition) games, but can also occur when playing 480p (Enhanced Definition) games. However, playing at a resolution of 480p (Enhanced Definition) or better typically eliminates most or all lag because the most strenuous process of scaling is the process of converting a 480i (interlaced) signal to a 480p (progressive) signal. The people that typically complain about lag even when playing in 480p (progressive) are DLP users, but in theory any HDTV that does not support 480p natively could still be affected. However, an HDTV signal should not experience lag on any HDTV. As a rule of thumb, you should stay away from DLP sets if you plan on playing a lot of timing-sensitive video games. So what resolution are my video games outputting? Pre-PS2 game systems: 240p/480i (240p is the same scan rate as 480i and therefore experiences the same problems) Playstation 2: 480i (most games), 480p (a few games) Gamecube : 480i (a few games), 480p (most games) X-Box: 480p (most games), 480i (a few games), 720p (a few games) X-Box 360: All X-Box and X-Box 360 games can be outputted to your choice of 480p, 1080i, or 720p. These are the resolutions that video game systems can output. For a full list of what game supports what resolution, a good source is http://www.hdtvarcade.com. What is the native resolution of my display? CRT HDTVs usually have two native resolutions and sometimes only one. Those resolutions are typically 480p and 1080i. Sometimes, it is only 1080i. THERE ARE NO CRT HDTVS THAT CAN DISPLAY A NATIVE RESOLUTION OF 480i. Plasma, LCD, and DLP HDTVs always have one native resolution. The native resolution is different for each set. Sometimes it's 720p, sometimes 1080i, sometimes 1080p, and sometimes something completely different. Example Chart Worst: You will notice lag. Better: There is lag, but it may be an acceptable level for you. Best: There is no lag. Example 1 (TV: Samsung DLP with 720p native resolution)* Worst: SNES Game (240p) --> Samsung DLP upscales to 720p --> Noticeable lag. Worst: PS2 Game (480i) --> Samsung DLP upscales to 720p --> Noticeable lag. Better: PS2 Game (480p) --> Samsung DLP upscales to 720p --> Fairly small lag. Better: X-Box Game (480p) --> Samsung DLP upscales to 720p --> Fairly small lag. Better: PS2 Game with Samsung DLP's Game Mode activated (480i) --> Fairly small lag. Best: X-Box Game (720p) --> Samsung displays the image directly --> Small lag. Best: X-Box 360 Game (720p) --> Samsung displays the image directly --> Small lag. Example 2 (TV: Sony CRT HDTV with both 480p and 1080i native resolutions): Better: SNES Game (240p) --> Sony CRT HDTV upscales to 480p --> Small lag. Better: PS2 Game (480i) --> Sony CRT HDTV upscales to 480p --> Small lag. Best: PS2 Game (480p) --> Sony CRT HDTV displays the image directly --> No lag. Best: X-Box Game (480p) --> Sony CRT HDTV displays image directly --> No lag. Best: X-Box Game (1080i) --> Sony CRT HDTV displays image directly --> No lag. Example 3 (TV: Sony LCD with 1080p native resolution) Worst: SNES Game (240p) --> Sony LCD upscales to 1080p --> Lag. Worst: PS2 Game (480i) --> Sony LCD upscales to 1080p --> Lag. Best: X-Box 360 game (720p) --> Sony LCD upscales to 1080p --> Small lag. Better: Any game on any system with Game Mode activated (any resolution) --> Fairly small lag. * Note that all Samsung DLPs pass the signal through its internal DCDi scaler which will result in lag even if you game at the TV's native resolution (Source: http://gear.ign.com/articles/744/744064p2.html) The only way to completely avoid lag on any system is to only play games at a resolution in which your HDTV doesn't have to do any scaling. As always, the BEST way to test for lag is to take your gaming set-up to your local electronics store and politely ask to test it on their HDTVs, which they shouldn't mind at all since you're a potential customer. Bring a time sensitive game, such as a fighting game, a rhythm game, or a golf/football game with a swinging/kicking meter. It's worth it to do a small trip to the store like this before you make such a large investment!