There seems to be a problem with my USB ports on my Lenovo IdeaPad Y580. On Windows 7 all four of them work just fine, but on CentOS 6.4 only one works. I have checked that the devices I used to test the ports work. On another computer (Acer Aspire 3690) all my USB ports work just fine under the exact same system (booted from HDD). Any ideas?