diff --git a/src/fpu/fpu.cpp b/src/fpu/fpu.cpp
index fc8b7901..70f4b66b 100644
--- a/src/fpu/fpu.cpp
+++ b/src/fpu/fpu.cpp
@@ -97,11 +97,23 @@ void FPU_ESC3_Normal(Bitu rm) {
 	switch (group) {
 	case 0x04:
 		switch (sub) {
-		case 0x03:				//FINIT
+		case 0x00:				//FNENI
+		case 0x01:				//FNDIS
+			LOG(LOG_FPU,LOG_ERROR)("8087 only fpu code used esc 3: group 4: subfuntion :%d",sub);
+			break;
+		case 0x02:				//FNCLEX FCLEX
+			FPU_FCLEX();
+			break;
+		case 0x03:				//FNINIT FINIT
 			FPU_FINIT();
 			break;
+		case 0x04:				//FNSETPM
+		case 0x05:				//FRSTPM
+			LOG(LOG_FPU,LOG_ERROR)("80267 protected mode (un)set. Nothing done");
+			FPU_FNOP();
+			break;
 		default:
-			LOG(LOG_FPU,LOG_WARN)("ESC 3:Unhandled group %d subfunction %d",group,sub);
+			E_Exit("ESC 3:ILLEGAL OPCODE group %d subfunction %d",group,sub);
 		}
 		break;
 	default:
diff --git a/src/fpu/fpu_instructions.h b/src/fpu/fpu_instructions.h
index 3b133566..e93ef964 100644
--- a/src/fpu/fpu_instructions.h
+++ b/src/fpu/fpu_instructions.h
@@ -28,4 +28,11 @@ static void FPU_FINIT(void) {
 	fpu.tags[5]=TAG_Empty;
 	fpu.tags[6]=TAG_Empty;
 	fpu.tags[7]=TAG_Empty;
+}
+static void FPU_FCLEX(void){
+	fpu.sw&=0x7f00;				//should clear exceptions
+};
+
+static void FPU_FNOP(void){
+	return;
 }
\ No newline at end of file