Researchers have found that combination anti-HIV therapy (multiple drugs given together) can help prevent AIDS-related illnesses and help people with AIDS live longer. In this study, the anti-HIV drug efavirenz (EFV) will be tested with 1 or 2 other protease inhibitors (PIs) to see which combination works best to treat HIV infection. EFV has been shown to limit the amount of HIV virus produced by infected cells.