All patients will receive 600 milligrams a day of efavirenz (a non-nucleoside reverse transcriptase inhibitor); 300 mg twice daily of abacavir (a nucleoside analog); and 1200 mg twice a day of amprenavir (a protease inhibitor). In addition to these drugs, six patients will receive 500 mg twice a day of ritonavir (a protease inhibitor); six patients will receive 200 mg twice a day of ritonavir; and 10 will receive 1250 mg twice a day of nelfinavir (a protease inhibitor).