The 40-year-old musician, who was sacked from the band in 2003, was discovered early yesterday morning.
The death is not being treated as suspicious.
Fellow Welsh musicians Manic Street Preachers were among those who expressed their shock as they praised the larger-than-life character.
"Whenever you met Stuart, you always walked away with a massive smile on your face," the band said in a statement. "Such a gigantic personality, which was reflected in his drumming. He really will be missed."
After his axing from Stereophonics – which he started with childhood friend and front man Kelly Jones – Cable became a radio presenter, with his most recent BBC Radio Wales broadcast only two days ago.
And he had been due to perform at this weekend's Download Festival at Donington Park with his new band Killing For Company.
Cable – known for his mop of shaggy, curly hair – had talked about how his drug use saw him become estranged from the rest of the band before they parted company.
The group originally formed as Tragic Love Company but landed a record deal after changing their name. They released debut album Word Gets Around in 1997, then scored a string of top 40 hits.