Dual monitors - difference in 'whiteness'

[Papillon]

I am running two identical Dell 1906FP monitors off an ATI Radeon X800 XL card with dual DVI outputs. Both monitors are on the factory settings, but the white on one of them is slightly duller than the other. It looks 'off' in comparison - not a huge amount, but when you look closely there's a difference. I've swapped the cables around, but the 'dull' monitor remains the same, so it's not the card.

Any suggestions?

Thanks.

 

[Papillon]

I've tried changing the settings, but it just goes a slightly different variation of its same 'white' if that makes sense.

Just to add, the second monitor is brand new today, and the original one is about a month old, so has had a few hours use. Would that make a difference?