diff --git a/src/cpu/cpu.c b/src/cpu/cpu.c
index a7e2e7b9a..843d5204d 100644
--- a/src/cpu/cpu.c
+++ b/src/cpu/cpu.c
@@ -592,7 +592,7 @@ CPU cpus_PentiumPro[] =
         {"Pentium II Overdrive 50",  CPU_PENTIUM2D, 5, 50000000, 1, 25000000, 0x1632, 0x1632, 0, CPU_SUPPORTS_DYNAREC | CPU_REQUIRES_DYNAREC, 4,4,3,3},
         {"Pentium II Overdrive 60",  CPU_PENTIUM2D, 6, 60000000, 1, 30000000, 0x1632, 0x1632, 0, CPU_SUPPORTS_DYNAREC | CPU_REQUIRES_DYNAREC, 6,6,3,3},
         {"Pentium II Overdrive 66",  CPU_PENTIUM2D, 6, 66666666, 1, 33333333, 0x1632, 0x1632, 0, CPU_SUPPORTS_DYNAREC | CPU_REQUIRES_DYNAREC, 6,6,3,3},
-        {"Pentium II Overdrive 75",  CPU_PENTIUM2D, 9, 75000000, 2, 25000000, 0x1632, 0x1632, 0, CPU_SUPPORTS_DYNAREC | CPU_REQUIRES_DYNAREC, 7,7,4,4},
+        {"Pentium II Overdrive 75",  CPU_PENTIUM2D, 9, 75000000, 2, 25000000, 0x654, 0x654, 0, CPU_SUPPORTS_DYNAREC | CPU_REQUIRES_DYNAREC, 7,7,4,4},
         {"Pentium II Overdrive 210",  CPU_PENTIUM2D, 22, 210000000, 4, 30000000, 0x1632, 0x1632, 0, CPU_SUPPORTS_DYNAREC | CPU_REQUIRES_DYNAREC, 17,17,7,7},
         {"Pentium II Overdrive 233",  CPU_PENTIUM2D, 24, 233333333, 4, 33333333, 0x1632, 0x1632, 0, CPU_SUPPORTS_DYNAREC | CPU_REQUIRES_DYNAREC, 21,21,10,1},
         {"Pentium II Overdrive 240",  CPU_PENTIUM2D, 25, 240000000, 4, 30000000, 0x1632, 0x1632, 0, CPU_SUPPORTS_DYNAREC | CPU_REQUIRES_DYNAREC, 24,24,12,12},
diff --git a/src/cpu/x86_ops_i686.h b/src/cpu/x86_ops_i686.h
index a61d27025..f1b824598 100644
--- a/src/cpu/x86_ops_i686.h
+++ b/src/cpu/x86_ops_i686.h
@@ -46,6 +46,8 @@ static int opSYSENTER(uint32_t fetchdat)
 	uint16_t sysenter_cs_seg_data[4];
 	uint16_t sysenter_ss_seg_data[4];
 
+        int cycles_old = cycles; UNUSED(cycles_old);
+
 #ifdef SYSENTER_LOG
 	pclog("SYSENTER called\n");
 #endif
@@ -74,20 +76,22 @@ static int opSYSENTER(uint32_t fetchdat)
 	flags &= ~0x0200;
 
 	CS = (cs_msr & 0xFFFC);
-	make_seg_data(sysenter_cs_seg_data, 0, 0xFFFFF, 11, 1, 0, 1, 1, 1, 0);
+	make_seg_data(sysenter_cs_seg_data, 0, 0xFFFFF, 11, 1, 0, 1, 1, 1, 1);
 	do_seg_load(&_cs, sysenter_cs_seg_data);
 	use32 = 0x300;
 
 	SS = ((cs_msr + 8) & 0xFFFC);
-	make_seg_data(sysenter_ss_seg_data, 0, 0xFFFFF, 3, 1, 0, 1, 1, 1, 0);
+	make_seg_data(sysenter_ss_seg_data, 0, 0xFFFFF, 3, 1, 0, 1, 1, 1, 1);
 	do_seg_load(&_ss, sysenter_ss_seg_data);
 	stack32 = 1;
 
-	cycles -= timing_call_pm;
+	cycles -= timing_call_rm;
 
 	optype = 0;
 
 	CPU_BLOCK_END();
+        PREFETCH_RUN(cycles_old-cycles, 7, -1, 0,0,cgate16 ? 2:0,cgate16 ? 0:2, 0);
+        PREFETCH_FLUSH();
 
 #ifdef SYSENTER_LOG
 	pclog("SYSENTER completed:\n");
@@ -105,6 +109,8 @@ static int opSYSEXIT(uint32_t fetchdat)
 	uint16_t sysexit_cs_seg_data[4];
 	uint16_t sysexit_ss_seg_data[4];
 
+        int cycles_old = cycles; UNUSED(cycles_old);
+
 #ifdef SYSEXIT_LOG
 	pclog("SYSEXIT called\n");
 #endif
@@ -130,21 +136,23 @@ static int opSYSEXIT(uint32_t fetchdat)
         cgate16 = cgate32 = 0;                                                  \
 
 	CS = ((cs_msr + 16) & 0xFFFC) | 3;
-	make_seg_data(sysexit_cs_seg_data, 0, 0xFFFFF, 11, 1, 3, 1, 1, 1, 0);
+	make_seg_data(sysexit_cs_seg_data, 0, 0xFFFFF, 11, 1, 3, 1, 1, 1, 1);
 	do_seg_load(&_cs, sysexit_cs_seg_data);
 	use32 = 0x300;
 
 	SS = CS + 8;
-	make_seg_data(sysexit_ss_seg_data, 0, 0xFFFFF, 3, 1, 3, 1, 1, 1, 0);
+	make_seg_data(sysexit_ss_seg_data, 0, 0xFFFFF, 3, 1, 3, 1, 1, 1, 1);
 	do_seg_load(&_ss, sysexit_ss_seg_data);
 	stack32 = 1;
 
 	flushmmucache_cr3();
 
-	cycles -= timing_call_pm;
+	cycles -= timing_iret_rm;
 
 	optype = 0;
 
+        flags_extract();
+        nmi_enable = 1;
 	CPU_BLOCK_END();
 
 #ifdef SYSEXIT_LOG
@@ -155,7 +163,9 @@ static int opSYSEXIT(uint32_t fetchdat)
 	pclog("Other information: eip=%08X esp=%08X eflags=%04X flags=%04X use32=%04X stack32=%i ECX=%08X EDX=%08X\n", cpu_state.pc, ESP, eflags, flags, use32, stack32, ECX, EDX);
 #endif
 
-	return 0;
+        PREFETCH_RUN(cycles_old-cycles, 1, -1, 0,2,0,0, 1);
+        PREFETCH_FLUSH();
+	return cpu_state.abrt;
 }
 
 static int opFXSAVESTOR_a16(uint32_t fetchdat)
diff --git a/src/hdd/hdd_ide_at.c b/src/hdd/hdd_ide_at.c
index 4e08941b2..b9c92ba99 100644
--- a/src/hdd/hdd_ide_at.c
+++ b/src/hdd/hdd_ide_at.c
@@ -221,6 +221,7 @@ void ide_irq_lower(IDE *ide)
 	ide->irqstat=0;
 }
 
+#if 0
 void ide_irq_update(IDE *ide)
 {
 	int pending = 0;
@@ -278,6 +279,8 @@ void ide_irq_update(IDE *ide)
 		}
 	}
 }
+#endif
+
 /**
  * Copy a string into a buffer, padding with spaces, and placing characters as
  * if they were packed into 16-bit values, stored little-endian.
@@ -926,7 +929,6 @@ void writeide(int ide_board, uint16_t addr, uint8_t val)
 			ide->lba_addr = (ide->lba_addr & 0x0FFFFFF) | ((val & 0xF) << 24);
 			ide_other->lba_addr = (ide_other->lba_addr & 0x0FFFFFF)|((val & 0xF) << 24);
 
-			ide_irq_update(ide);
 			return;
 
 		case 0x1F7: /* Command register */
@@ -1237,9 +1239,10 @@ ide_bad_command:
 				idecallback[ide_board] = 0;
 				timer_update_outstanding();
 				ide->atastat = ide_other->atastat = BUSY_STAT;
+				ide_irq_lower(ide);
+				ide_irq_lower(ide_other);
 			}
 			ide->fdisk = ide_other->fdisk = val;
-			ide_irq_update(ide);
 			return;
 	}
 }
diff --git a/src/pci.c b/src/pci.c
index 5bd236856..21ac26687 100644
--- a/src/pci.c
+++ b/src/pci.c
@@ -681,7 +681,7 @@ void trc_init(void)
 {
 	trc_reg = 0;
 
-	io_sethandler(0x0cf9, 0x0001, trc_read, NULL, NULL, trc_write, NULL, NULL, NULL);
+	// io_sethandler(0x0cf9, 0x0001, trc_read, NULL, NULL, trc_write, NULL, NULL, NULL);
 }
 
 void pci_init(int type)