Dried out roots - is there hope?

[acco]

I was at a plant store the other day and there was a bin full of orchid divisions for a couple bucks each. I couldn't help it and took home three (I think two are cattleyas and the other might be an oncidium).

However, my guess is they all have been unpotted for quite some time... the roots were pretty much all completely dried out and dead - the outer parts were coming off revealing the stringy part inside. Two of them looked like they had little new roots starting to grow but the third didn't. Do these guys have any hope of survival? Their leaves are still green and non-wilty, if a little banged up looking from being in the bin.

What could I do to help them out? I potted them all and watered and that's all I've done so far (I did cut off the dead roots, though they don't have much to anchor themselves with now)

Thanks!