I've just bought 2 identical 23" monitors, Acer V233H to be precise.
On my graphics card (ATI Radeon HD4870), I have 3 outputs. 1 HDMI, 1 DVI (or maybe DVI-I?) and another one that I haven't seen before (it's not VGA though).
So 1 of the monitors is connected directly via DVI, where as the other one is connected via an DVI-to-HDMI converter and inside the HDMI port of my graphics card.
The color difference between them is quite significant, the HDMI one is a lot cleaner and brighter even though I've reset all settings (both on the ATI card and the monitor).
Could this really be due to the converter, or am I missing something obvious?