I am surprised the monitor companies haven't picked up on this yet and somehow build this feature into their screens. Is there any downside to it? maybe reduction in life of the monitor due to having the lightboost on all the time or something?
The main disadvantage of LightBoost is color quality and some loss of brightness. LightBoost can produce somewhat degraded color, but with some careful adjustment (via nVidia Control Panel, since some monitor settings are locked), you can get 80% of the picture quality back. TFT Central's article shows that they were able to get almost the same contrast ratio with LightBoost as with non-LightBoost. cpkeeper can also force games to use the calibration too, since games override it.
Brightness loss isn't a big problem for my eyes because these monitors are already WAY too bright (350cd/m2) so loss of brightness during LightBoost (it's not as bright as Brightness=100%, more closer to Brightness=50%) is not a big problem.
Flicker-sensitive people may not like LightBoost (especially if you hated CRT). But for FPS players who didn't mind a high-refresh rate CRT, it's a less evil flicker than PWM. I get less eyestrain with LightBoost than with PWM. The one-pulse-per-refresh produces a pleasing zero motion blur effect. TFT Central's article explains this too, as does
LCD Motion Artifacts 101; if you are used to a high-end 120Hz CRT, then you won't mind 120Hz LightBoost.
No wear and tear. LightBoost is an intentional feature built into a monitor, but was force-bundled with 3D Vision. The new tweaks simply unbundles LightBoost from 3D glasses. Letting you get LightBoost benefit for 2D, without buying a 3D Vision kit. (nVidia certainly isn't complaining: It has caused a lot of Titan sales!)
If you want good out-of-box LightBoost color, get the ASUS VG278H since there's no purple tint like some VG248QE's have. Also, XL2420T and VG278HE (the 'HE', not 'H') have an increased checkerboard pixel pattern artifact during fast motion during lightboost, which is not noticeable to everyone, but bothered a few (e.g. hazmatm compared VG278H and VG278HE on overclock.net and preferred the VG278H). The manufacturers need to re-enable LightBoost picture adjustments.
And if you end up hate LightBoost, you can always turn off LightBoost. The monitors still do a great job of 120Hz and 144Hz. So not a waste of money. See
testimonials and
media coverage.