Those 4ms-2ms responce times are mute, because an 8ms LCD is capable of 125Hz or 125fps, but because of the latency between the graphics card & the monitor/VSync enabled the graphics card has to wait until the LCD is ready for the next frame. VSync caps your frames to what your refresh rate is- 60Hz = 60fps cap, 75Hz =75fps cap. If image tearing don't bother you that much then with VSync off, your monitor is able run as fast as it was designed to run. Also if you can keep your fps closer to your refresh rate than image tearing is not noticed as much, just remember that refresh rate for an LCD is actuly responce time/latency. A lot of LCD makers cheat in how they messure responce times, the right way is how long it takes for one pixel to turn on-off and back on. Some only messure on-off times in doing so cheating!