For the 7950, you might be better off going with UBuntu 14.04 and using the fglrx 15.12 (they are in one of the Ubunty repositories with "-302" as part of the name) drivers.

 I'm not sure if the "PRO" stuff supports older cards, though in theory it SHOULD work with anything GCN.


 Muddybit - it's called "lots of folks building new rigs adding to the hashrate raising the difficulty because of the crazy-high ZEC price rise the last 2 months or so" - so yes, you're right. 9-)