Dual Monitor Configuration - HD6850

Wasn't sure if this should go in hardware or here seeming as it's about monitors as well as the graphics card, but yea.. move if needed I guess :)

So.. today I got a new monitor. One of those korean 27" 2560x1440 displays, the QNIX qx2710. I have also an LG 22" old flat panel screen, and a 20" hdtv that's got DVI on it. For years I've used my 22" as my main and my 20" tv as the second screen (extended, not duplicated)

Today is where it got weird, although I THINK I've worked out what is going on, I'd like some people in the know to chime in as my expertise is software, not hardware. The new monitor works beautifully (typing this on it now.. amazingly good considering it was £200 brand new!), it's one of those panel only single input things that make your GPU do all the work, whereas some don't (from what little I understand of monitor complexities). It appears my 22" is also one of those, or at least I'm guessing so, as it's a single input also and was pretty cheap when I got it years ago. My GPU (hd6850 sapphire toxic edition 1gb) has a bunch of ports on it, two mini display port, plus two DVIs, and a hdmi.

The 27" and the 22" (both single input monitors) will not work together, on ports that work in other configurations, with wires that work in other configurations, etc. Here's what I've tested. Top herein refers to the top DVI port on the GPU, which I assume is the 'main' or w/e, and bottom the other one.

27 (top) + 22 (bottom) = 27 only works, 22 undetectable
22 (top) + 27 (bottom) = 22 only works, 27 detectable in device manager but unable to extend the monitor to it. GPU control panel comes up with something like 'this is unavailable in your current monitor configuration'
22 (bottom) = doesn't work
27 (bottom) = doesn't work
20 (bottom) = works fine
27 (top) + 20 (bottom) = both work fine
27 (top) + 20 (hdmi) = both work fine)

What this leads me to believe, is that the 'bottom' port isn't as powerful as the top port, and cant get all the GPU juice to make a single input power hungry monitor work. The TV I'm guessing has loads of it's own processing power as being a TV, it'd normally just be hooked up to a TV input which obvs has no processing power as it's just a signal in. Am I right in thinking this, at least to some extent? (I'm guessing on this so don't bite if I make a stupid remark out of idiocy :) )

What I would like to do.. Is have the 27 (top), 22 (bottom), and 20 (hdmi). They'd rarely be used at the same time, and definitely not for anything GPU intensive (i.e gaming) at the same time, I only want three screens because I want two when browsing the internet/doing work at the same time, and the third monitor to go over to the other side of my room so I can watch things from my bed. Is this at all possible with my current configuration, or is handling two of these lazy monitors on the same GPU impossible? or is it an issue with one of the DVI ports, and I could maybe use an adapter for one of the mini display ports to the VGA (converted to DVI currently with an adapter thingy) on the 22" so that it'd work there?

I know that's a boat load of text, but I'm hoping someone has the time to read it all and offer some insight. thankyou soo much in advance everyone :)