Since the latst 3 updates (at least) , my wallet takes forever to sync .Disk usage is ridiculously high and the computer slows down
I have ubuntu 14.04 running on I5 with 8gb of memory and 300G of disk . I tried with another disk same problem

And now with 0.8.6 it cannot sync 
E1019 10:53:14.699769 core/blockchain.go:1170] Bad block #2462853 (0xd7929a629b2d1226ddab5c8be6c7949b4fa3cbcafa6f0871f99b437454969363)
E1019 10:53:14.699794 core/blockchain.go:1171]     gas used error (463960 / 454930)
It's  stucked there

( i have restarted from scratch    geth removedb and after geth --cache 1048 --fast )

Any help

Thanks