This study will compare different treatments for HIV infection to see which works best to lower the amount of the HIV virus and raise the number of CD4+ cells in patients with a measurable amount of HIV virus in the blood after at least 16 weeks on first assigned anti-HIV therapy. A patient's current anti-HIV therapy must contain one of the following drugs called protease inhibitors (PI) which are FDA approved: Crixivan/Indinavir, Norvir/Ritonavir or Viracept/Nelfinavir. Protease Inhibitors are a group of anti-HIV drugs that decrease the amount of HIV in the blood and help prevent HIV from spreading from one cell to another. The drugs that will be used in this study are soft gelatin saquinavir/fortovase, Efavirenz/Sustiva. Efavirenz is an investigational drug that has not yet been approved by the FDA. It belongs to a group of anti-HIV drugs known as non-nucleoside reverse transcriptase inhibitors (NNRTIs) and has been used through expanded access or compassionate use programs and in research studies.