To be precise he isn't talking about monitor lag, he is talking about head mounted displays.

That tweet follows another one complaining that the Sony HMZ-T1 had 50ms more lag than another HMD that he has tested (which probably also has high latency), and so I am sure his comment is completely accurate.

Edit: didn't read beyond the silly starting question to see JC himself had answered with the facts, so worth a read anyway.

The game controller updates at 250 hz, but there is no direct way to measure the latency on the input path (I wish I could still wire things to a parallel port and use in/out Sam instructions). As a control experiment, I do the same test on an old CRT display with a 170hz vertical retrace. Aero and multimon can introduce extra latency, but under optimal conditions you will usually see a color change starting at some point on the screen (vsync disabled) two 240 hz frames after the button goes down. It seems there is 8ms or so of latency going through the USB HID processing, but I would like to nail this down better in the future.

It is not uncommon to see desktop LCD monitors take 10+ 240hz frames to show a change on the screen. The Sony HMZ averaged around 18 frames, or 70+ total milliseconds.

This was in a multimonitor setup, so a couple frames are the driver's fault.

Some latency is intrinsic to a technology. LCD panels take 4-20 milliseconds to actually change, depending on the technology. Single chip LCOS displays must buffer one video frame to convert from packed pixels to sequential color planes. Laser raster displays need some amount of buffering to convert from raster return to back and forth scanning patterns. A frame-sequential or top-bottom split stereo 3D display can't update mid frame half the time.

OLED displays should be among the very best, as demonstrated by an Emagin z8, which is comparable to a 60hz CRT in latency, better than any other non-CRT I tested.

edit and note: the emagin are "3d goggles", not a monitor. oh, and they cost 1500€ upwards :d

he can make his own console instead of spaceships where everything works in sync, which wouldnt really make much difference, unless you get a 250hz monitor with your £3000 console, tv are only 60-65hz

control pads probaly only update alot faster for the analog sticks that are still analog

Saw this the other day. <3 John Carmack.