Calibrating two screens identical

Question

I have an 24" iMac, about a year old, and a 2-3 yr old Eizo Flexscan L767 attached as a extra screen. I do a lot of photography, so want my screens calibrated.
I use a gretagMacbeth calibration gadget and Eye One software.
After calibration, my iMac screen still looks a lot brighter and more saturated then the Eizo screen.
I consulted a learned friend who suggested the following:
The reason (probably) your monitors look different is because each monitor requires a separate LUT (look up table) to hold the profile you make for it. Once both monitors are properly profiled they should be very similar. LUT’s are provided by your graphics card. Some only have one, some have two. One is more common, especially the built in graphics cards..
The most important thing to find out is does your graphics card have two LUT’s? Maybe you can look this up or ask Mac support? And if not lets look into what graphic card will. Chances are you can use the current graphics card for one monitor (built in monitor) and just get a inexpensive secondary card for your EIZO.<
End of first quote.
I am not a techie, so wonder if anyone can tell me here if my card supports 2 LUTs?
My card is : ATI Radeon HD 2600 Pro:
Full details at the end of this post.
further comment from my friend:
<div class="jive-quote">The problems I’ve had with ATI cards is the driver support. Always issues. Then I went to Nvidia which is mostly a gaming card, but it has excellent drivers. No more issues. I put in one 7950GT card.. discovered it only had one LUT (even though it had two DVI outs), so I got another and now I run two graphics cards. . Same model/series graphics cards, same model/series monitors. I use the second DVI to run non-color profiled devices like my 50” HDTV (for family slide shows) and DLP projector.<</div>
So if my Ati has only one LUT, is it possible to replace it with one that supports 2 LUT, OR can i add another one?
In terms of my service options, I live in Thailand, bought my iMac in Bangkok, and have it serviced there. But since I know and understand little of Graphics cards and LUT's, passing on this issue to a service person with limited english may be a problem.

Answer 1

Thanks Pete,
I have an Eizo so will have to use that.
I spoke to my Apple dealer a few days ago, and he said that, contrary to what Nicholas wrote above, the Graphics card does NOT support two different LookUpLists. Two computer will give them different names, but when you look at the two profiles it produces, you will see that the numbers are actually mostly the same. Except for two strings of ASCII code, but they are likely to represent text identifying the monitor. I assume that unless I tell my computer which specific profile to use, it will choose the last one, which means that if today the last screen profiled is the iMac screen, my Eizo will also display according to the iMac calibration. This may well be a good explanation for some uneven printing I have been experiencing lately.
Sometimes I wonder if it wouldn't be useful if actual Apple tech staff would have an input in this board, as tech staff on other brand related boards sometimes have.