diff --git a/src/386.c b/src/386.c
index 25ee0e8..ce077bb 100644
--- a/src/386.c
+++ b/src/386.c
@@ -227,7 +227,7 @@ void exec386(int cycs)
         {
                 cycdiff=0;
                 oldcyc=cycles;
-                timer_start_period(cycles);
+                timer_start_period(cycles << TIMER_SHIFT);
 //                pclog("%i %02X\n", ins, ram[8]);
                 while (cycdiff<100)
                 {
@@ -375,6 +375,6 @@ opcodestart:
                 
                 tsc += cycdiff;
                 
-                timer_end_period(cycles);
+                timer_end_period(cycles << TIMER_SHIFT);
         }
 }
diff --git a/src/386_dynarec.c b/src/386_dynarec.c
index 71a60b3..c338813 100644
--- a/src/386_dynarec.c
+++ b/src/386_dynarec.c
@@ -1215,7 +1215,7 @@ void exec386_dynarec(int cycs)
                 cycles += 1000;
                 cycles_start = cycles;
 
-                timer_start_period(cycles);
+                timer_start_period(cycles << TIMER_SHIFT);
 //        output=3;
         while (cycles>0)
         {
@@ -1510,7 +1510,7 @@ inrecomp=0;
                         }
                 }
         }
-                timer_end_period(cycles);
+                timer_end_period(cycles << TIMER_SHIFT);
                 cycles_main -= (cycles_start - cycles);
         }
 }
diff --git a/src/808x.c b/src/808x.c
index 97d5a18..3962d42 100644
--- a/src/808x.c
+++ b/src/808x.c
@@ -20,6 +20,7 @@
 #include "timer.h"
 #include "x86.h"
 
+int xt_cpu_multi;
 int nmi = 0;
 
 int nextcyc=0;
@@ -807,7 +808,7 @@ void clockhardware()
         
         current_diff += diff;
   
-        timer_end_period(cycles);      
+        timer_end_period(cycles*xt_cpu_multi);
 }
 
 static int takeint = 0;
@@ -1084,7 +1085,7 @@ void execx86(int cycs)
 //                if (pc==0x96B && cs==0x9E040) { printf("Hit it\n"); output=1; timetolive=150; }
 //                if (pc<0x8000) printf("%04X : %04X %04X %04X %04X %04X %04X %04X %04X %04X %04X %04X %04X %02X %04X %i\n",pc,AX,BX,CX,DX,cs>>4,ds>>4,es>>4,ss>>4,DI,SI,BP,SP,opcode,flags,disctime);
                 cycdiff=cycles;
-                timer_start_period(cycles);
+                timer_start_period(cycles*xt_cpu_multi);
                 current_diff = 0;
                 cycles-=nextcyc;
 //                if (instime) pclog("Cycles %i %i\n",cycles,cycdiff);
diff --git a/src/cpu.c b/src/cpu.c
index 8376d8b..43636cc 100644
--- a/src/cpu.c
+++ b/src/cpu.c
@@ -109,7 +109,7 @@ static struct
 CPU cpus_8088[] =
 {
         /*8088 standard*/
-        {"8088/4.77",    CPU_8088,  0,  4772727, 1, 0, 0, 0, 0, 0},
+        {"8088/4.77",    CPU_8088,  0,  4772728, 1, 0, 0, 0, 0, 0},
         {"8088/8",       CPU_8088,  1,  8000000, 1, 0, 0, 0, 0, 0},
         {"8088/10",      CPU_8088,  2, 10000000, 1, 0, 0, 0, 0, 0},
         {"8088/12",      CPU_8088,  3, 12000000, 1, 0, 0, 0, 0, 0},
@@ -120,16 +120,16 @@ CPU cpus_8088[] =
 CPU cpus_pcjr[] =
 {
         /*8088 PCjr*/
-        {"8088/4.77",    CPU_8088,  0,  4772727, 1, 0, 0, 0, 0, 0},
+        {"8088/4.77",    CPU_8088,  0,  4772728, 1, 0, 0, 0, 0, 0},
         {"",             -1,        0, 0, 0, 0}
 };
 
 CPU cpus_8086[] =
 {
         /*8086 standard*/
-        {"8086/7.16",    CPU_8086,  1,  3579545*2,     1, 0, 0, 0, 0, 0},
+        {"8086/7.16",    CPU_8086,  1, 14318184/2,     1, 0, 0, 0, 0, 0},
         {"8086/8",       CPU_8086,  1,  8000000,       1, 0, 0, 0, 0, 0},
-        {"8086/9.54",    CPU_8086,  1, (3579545*8)/3,  1, 0, 0, 0, 0, 0},
+        {"8086/9.54",    CPU_8086,  1,  4772728*2,     1, 0, 0, 0, 0, 0},
         {"8086/10",      CPU_8086,  2, 10000000,       1, 0, 0, 0, 0, 0},
         {"8086/12",      CPU_8086,  3, 12000000,       1, 0, 0, 0, 0, 0},
         {"8086/16",      CPU_8086,  4, 16000000,       1, 0, 0, 0, 0, 0},
diff --git a/src/cpu.h b/src/cpu.h
index fb5d678..51afb9b 100644
--- a/src/cpu.h
+++ b/src/cpu.h
@@ -103,3 +103,5 @@ void cpu_RDMSR();
 void cpu_WRMSR();
 
 extern int cpu_use_dynarec;
+
+extern int xt_cpu_multi;
diff --git a/src/intel.c b/src/intel.c
index bba57ca..67d06f4 100644
--- a/src/intel.c
+++ b/src/intel.c
@@ -1,4 +1,5 @@
 #include "ibm.h"
+#include "cpu.h"
 #include "io.h"
 #include "mem.h"
 #include "pit.h"
diff --git a/src/pc.c b/src/pc.c
index 57ae3d9..089c48f 100644
--- a/src/pc.c
+++ b/src/pc.c
@@ -182,7 +182,10 @@ void pc_reset()
         pit_reset();
         serial_reset();
 
-        setpitclock(models[model].cpu[cpu_manufacturer].cpus[cpu].rspeed);
+        if (AT)
+                setpitclock(models[model].cpu[cpu_manufacturer].cpus[cpu].rspeed);
+        else
+                setpitclock(14318184.0);
         
 //        sb_reset();
 
@@ -463,7 +466,10 @@ void fullspeed()
         if (!atfullspeed)
         {
                 printf("Set fullspeed - %i %i %i\n",is386,AT,cpuspeed2);
-                setpitclock(models[model].cpu[cpu_manufacturer].cpus[cpu].rspeed);
+                if (AT)
+                        setpitclock(models[model].cpu[cpu_manufacturer].cpus[cpu].rspeed);
+                else
+                        setpitclock(14318184.0);
 //                if (is386) setpitclock(clocks[2][cpuspeed2][0]);
 //                else       setpitclock(clocks[AT?1:0][cpuspeed2][0]);
         }
@@ -473,13 +479,10 @@ void fullspeed()
 
 void speedchanged()
 {
-        if (atfullspeed)
-        {
-                cpuspeed2=cpuspeed;
+        if (AT)
                 setpitclock(models[model].cpu[cpu_manufacturer].cpus[cpu].rspeed);
-//                if (is386) setpitclock(clocks[2][cpuspeed2][0]);
-//                else       setpitclock(clocks[AT?1:0][cpuspeed2][0]);
-        }
+        else
+                setpitclock(14318184.0);
         mem_updatecache();
         nvr_recalc();
 }
diff --git a/src/pit.c b/src/pit.c
index c89ac95..54ccd3d 100644
--- a/src/pit.c
+++ b/src/pit.c
@@ -13,7 +13,7 @@
 #include "pit.h"
 #include "timer.h"
 #include "video.h"
-
+#include "model.h"
 /*B0 to 40, two writes to 43, then two reads - value does not change!*/
 /*B4 to 40, two writes to 43, then two reads - value _does_ change!*/
 //Tyrian writes 4300 or 17512
@@ -36,6 +36,10 @@ void setpitclock(float clock)
         isa_timing = clock/8000000.0;
         bus_timing = clock/(double)cpu_busspeed;
         video_updatetiming();
+//        pclog("PITCONST=%f CGACONST=%f\n", PITCONST, CGACONST);
+//        pclog("CPUMULTI=%g\n", ((14318184.0*(double)(1 << TIMER_SHIFT)) / (double)models[model].cpu[cpu_manufacturer].cpus[cpu].rspeed));
+        
+        xt_cpu_multi = (int)((14318184.0*(double)(1 << TIMER_SHIFT)) / (double)models[model].cpu[cpu_manufacturer].cpus[cpu].rspeed);
 //        pclog("egacycles %i egacycles2 %i temp %f clock %f\n",egacycles,egacycles2,temp,clock);
 /*        if (video_recalctimings)
                 video_recalctimings();*/
diff --git a/src/timer.c b/src/timer.c
index df82f23..052f072 100644
--- a/src/timer.c
+++ b/src/timer.c
@@ -43,7 +43,7 @@ void timer_process()
                 enable[c] = *timers[c].enable;
                 if (*timers[c].enable)
                 {
-                        *timers[c].count = *timers[c].count - (diff << TIMER_SHIFT);
+                        *timers[c].count = *timers[c].count - diff;
                         if (*timers[c].count <= 0)
                                 process = 1;
                 }
diff --git a/src/timer.h b/src/timer.h
index 264c137..7c8d4f5 100644
--- a/src/timer.h
+++ b/src/timer.h
@@ -6,7 +6,7 @@ extern int timer_start;
 #define timer_end_period(cycles) 			\
 	do 						\
 	{						\
-                int diff = timer_start - cycles;        \
+                int diff = timer_start - (cycles);      \
 		timer_count -= diff;			\
                 timer_start = cycles;                   \
 		if (timer_count <= 0)			\
@@ -16,14 +16,23 @@ extern int timer_start;
 		}					\
 	} while (0)
 
-#define timer_clock()                                   \
-	do 						\
-	{						\
-                int diff = timer_start - cycles;        \
-		timer_count -= diff;			\
-                timer_start = cycles;                   \
-		timer_process();		        \
-        	timer_update_outstanding();	        \
+#define timer_clock()                                                   \
+	do 						                \
+	{						                \
+                int diff;                                               \
+                if (AT)                                                 \
+                {                                                       \
+                        diff = timer_start - (cycles << TIMER_SHIFT);   \
+                        timer_start = cycles << TIMER_SHIFT;            \
+                }                                                       \
+                else                                                    \
+                {                                                       \
+                        diff = timer_start - (cycles * xt_cpu_multi);   \
+                        timer_start = cycles * xt_cpu_multi;            \
+                }                                                       \
+		timer_count -= diff;			                \
+		timer_process();		                        \
+        	timer_update_outstanding();	                        \
 	} while (0)
 
 void timer_process();