All eight men who had unprotected anal sex with a HIV-positive man, Stuart James McDonald, 43 tested positive for HIV in 2005, the South Australian Supreme Court led by justice Margaret Nyland has heard.

McDonald had told the court, at the beginning of his trial that he met four of his victims through an online site called Gaydar, three at an Adelaide beat, Veale Gardens and one at a gay boarding house.

Prosecutor Sandi McDonald told the court that each of the men who had the misfortune to have sex with the HIV-positive McDonald is HIV positive.

Some of the men believed that McDonald was using a condom, but they realized later that he had failed to do so or had removed it during sex.

Prior to moving to SA in 2005, McDonald lived with a boyfriend in NSW and had failed to inform his partner of his condition.

His partner later was tested positive for HIV - due to unprotected sex with McDonald, said Ms McDonald.

To suggest that he did not know he had infected his former boyfriend, would be absurd, said Ms McDonald.

A witness testified that McDonald left out the detail that he was HIV-positive on his Gaydar web site profile, informed the prosecutor.

Ms McDonald said, There was no way he was going to do it, because no one would want to be with him.

When questioned by some of his victims, he had lied and said, he was clean too.

McDonald had pleaded not guilty to all eight counts of endangering life. The trial continues.