[AS PER AMENDMENT 2/27/98: Patients with HIV RNA less than 500 copies/ml currently on triple therapy with amprenavir + 3TC + ZDV (or d4T if ZDV-intolerant) are treated on ARM A. Patients with HIV RNA greater than or equal to 500 copies/ml, who have been intolerant to a regimen containing amprenavir or who were previously enrolled on ACTG 347 who elected to receive a treatment regimen other than amprenavir + ZDV (or d4T) + 3TC or IDV + NVP + 3TC + d4T or other regimens are assigned to Arm C.