Hi I know this might be a futile attempt, but please read: I've now used the Suface Pro since December. I've had this problem with new LED backlit displays which use Pulse Width Moduluation (PWM) for dimming the backlight. This means, that the backlight is actually not dimmed, but is flashed on and off with typically 180-600 Hz, but some manufacturers use even 8000 Hz. This causes eye strain and the SP2 does have this flicker also. This is cheaper to do this way, as when the LED is actually dimmed, it will change the color temperature and cause problems in the color accuracy. I have been able to change all my displays and televisions to such models, that do not use PWM at all, or do not use it at 100 % brightness. The PWM frequency is measured by sites like TFTCentral and Prad.de in monitor reviews. Manufacturers like Eizo and Benq are advertizing flicker free displays - meaning, this starts to be a recognized problem. There are articles in mainstream media on how to reduce eye strain from working at a computer etc. But since I do not have PWM in any of my devices (except Suface Pro 2), my eye strain and red eyes have completely disappeared. I enjoyed about a years time of no eye strain, no matter how much I used my computers or SmartPhone (Galaxy S2) Now when I purchased the SP2, the eye strain came back. I always have dry and kind of swollen feeling eyes in the morning, if I have been using the SP2 for 2 to 3 hours in the evening. When I don't use it for a couple of days, my eyes are problem free. I know that many people think that it is because of the small text, the PPI of the screen or bad eyesight. I don't wan to go any deeper into that discussion, but it's not. I is the flickering of the display. Mind you, it's a flicker that most people, myself including, cannot detect visually, but the optic nerve does, which causes the irritation. This is a widely recognized problem with several forum discussion even at Apple forums. So why I'm writing this? It's because I have not been able to find out the PWM fequency of SP2. The flicker is not detectable via the DSLR test but is visible if filming the screen at 25 frames per second with a shutter speed of 4000. Flicker is not present in any of the other displays that I use, by these tests or by the tests that have been done with professional oscilloscopes or similar. It would be beneficial to know the frequency and if the might be something to do about it, e.g. at display driver level. I also would like to address this problem, because there are cleary people who do get eye strain from SP2 and the problem would be so easy to fix - just do not use PWM, use some other non-flickering technology in the backlight dimming. I've been thinking of how to convey this issue to Microsoft and try to ensure that the next verson of SP does have a non-flickering display, but I do not think it is an easy task. Has anyone else experienced eye strain with heavy usage of SP or SP2?