I have a dual screen setup on an HP Pro 3300 (Pentium G620 2.6GHZ, 3GB RAM, 500GB HDD) running Windows 7 Professional x64 and using a ATI Radeon HD 5450 (both monitors are connected to the GFX Card, not the on-board Graphics), the monitors are both Samsung SyncMaster 723N's (17" LCD's). Basically a couple of months ago I noticed the brightness on the left hand monitor had gone darker than the right. I fiddled with settings in "Calibrate Display Colour" in the Control Panel and got the brightness back to matching the other screen. A few weeks later the same thing happened, the left hand screen was darker than the right so again I changed some settings and all was well. But it's happened today for a third time and I was wondering really if anyone could advise as to what might be causing this? I've tried replacing the monitor but that didn't seem to help. It's obviously a relatively trivial issue, but it's most annoying!
Thanks in advance!