On 7790(260x) not speedup. 
Miner does not set optimal "-h" and "-a" options for many cards. It's because I don't have all cards here. Post first 20-30 log lines here so I can see how many compute units your card has and what's its name. Use "m" key to adjust "-h" value, or try to change "-h" values directly if OpenCL crashes.
This version requires some time to find optimal settings.
Everyone can post optimal "-h" and "-a" values for your cards here (and also card name as it is displayed and number of compute units), I will use this data to improve miner. Right now it knows only 290x,280x,270x and 6950 cards.
Same card, can you enhance its output or it has reached its maximum?
Try "-a 4".
NOTE: 1GB cards cannot show good results anyway and in most cases you will not see any improvements.
I got some good results on my 6950 1GB with
But for 6770 1GB and win 8.1 i have no luck
Btw i also have no luck with R9 290 on Win 8.1, so i think it's some sort of OS problem, cause every rigs with win 7 increasing hashrate (R9 270, 7850, 6950, 5870 and very little on 7950)