diff --git a/src/vid_ati_mach64.c b/src/vid_ati_mach64.c
index 4270f1a..3f0ff01 100644
--- a/src/vid_ati_mach64.c
+++ b/src/vid_ati_mach64.c
@@ -299,6 +299,7 @@ void mach64_recalctimings(svga_t *svga)
                 svga->ma_latch = (mach64->crtc_off_pitch & 0x1fffff) * 2;
                 svga->linedbl = svga->rowcount = 0;
                 svga->split = 0xffffff;
+                svga->vblankstart = svga->dispend;
 //                svga_htotal <<= 1;
 //                svga_hdisp <<= 1;
                 svga->rowoffset <<= 1;                
diff --git a/src/vid_et4000w32.c b/src/vid_et4000w32.c
index 2bffd96..03adf4b 100644
--- a/src/vid_et4000w32.c
+++ b/src/vid_et4000w32.c
@@ -236,12 +236,13 @@ void et4000w32p_recalctimings(svga_t *svga)
 //        pclog("Recalc %08X  ",svga_ma);
         svga->ma_latch |= (svga->crtc[0x33] & 0x7) << 16;
 //        pclog("SVGA_MA %08X %i\n", svga_ma, (svga_miscout >> 2) & 3);
-        if (svga->crtc[0x35] & 0x02)     svga->vtotal     += 0x400;
-        if (svga->crtc[0x35] & 0x04)     svga->dispend    += 0x400;
-        if (svga->crtc[0x35] & 0x08)     svga->vsyncstart += 0x400;
-        if (svga->crtc[0x35] & 0x10)     svga->split      += 0x400;
-        if (svga->crtc[0x3F] & 0x80)     svga->rowoffset  += 0x100;
-        if (svga->crtc[0x3F] & 0x01)     svga->htotal     += 256;
+        if (svga->crtc[0x35] & 0x01)     svga->vblankstart += 0x400;
+        if (svga->crtc[0x35] & 0x02)     svga->vtotal      += 0x400;
+        if (svga->crtc[0x35] & 0x04)     svga->dispend     += 0x400;
+        if (svga->crtc[0x35] & 0x08)     svga->vsyncstart  += 0x400;
+        if (svga->crtc[0x35] & 0x10)     svga->split       += 0x400;
+        if (svga->crtc[0x3F] & 0x80)     svga->rowoffset   += 0x100;
+        if (svga->crtc[0x3F] & 0x01)     svga->htotal      += 256;
         if (svga->attrregs[0x16] & 0x20) svga->hdisp <<= 1;
         
         switch ((svga->miscout >> 2) & 3)
diff --git a/src/vid_s3_virge.c b/src/vid_s3_virge.c
index 198b09a..5492467 100644
--- a/src/vid_s3_virge.c
+++ b/src/vid_s3_virge.c
@@ -99,6 +99,7 @@ typedef struct virge_t
         } streams;
 } virge_t;
 
+static void s3_virge_recalctimings(svga_t *svga);
 static void s3_virge_updatemapping(virge_t *virge);
 
 static void s3_virge_bitblt(virge_t *virge, int count, uint32_t cpu_dat);
@@ -161,6 +162,7 @@ static void s3_virge_out(uint16_t addr, uint8_t val, void *p)
                 if (svga->seqaddr >= 0x10)
                 {
                         svga->seqregs[svga->seqaddr & 0x1f]=val;
+                        s3_virge_recalctimings(svga);
                         return;
                 }
                 if (svga->seqaddr == 4) /*Chain-4 - update banking*/
@@ -321,12 +323,13 @@ static void s3_virge_recalctimings(svga_t *svga)
 {
         virge_t *virge = (virge_t *)svga->p;
 
-        if (svga->crtc[0x5d] & 0x01) svga->htotal     += 0x100;
-        if (svga->crtc[0x5d] & 0x02) svga->hdisp      += 0x100;
-        if (svga->crtc[0x5e] & 0x01) svga->vtotal     += 0x400;
-        if (svga->crtc[0x5e] & 0x02) svga->dispend    += 0x400;
-        if (svga->crtc[0x5e] & 0x10) svga->vsyncstart += 0x400;
-        if (svga->crtc[0x5e] & 0x40) svga->split      += 0x400;
+        if (svga->crtc[0x5d] & 0x01) svga->htotal      += 0x100;
+        if (svga->crtc[0x5d] & 0x02) svga->hdisp       += 0x100;
+        if (svga->crtc[0x5e] & 0x01) svga->vtotal      += 0x400;
+        if (svga->crtc[0x5e] & 0x02) svga->dispend     += 0x400;
+        if (svga->crtc[0x5e] & 0x04) svga->vblankstart += 0x400;
+        if (svga->crtc[0x5e] & 0x10) svga->vsyncstart  += 0x400;
+        if (svga->crtc[0x5e] & 0x40) svga->split       += 0x400;
         svga->interlace = svga->crtc[0x42] & 0x20;
 
         if ((svga->crtc[0x67] & 0xc) != 0xc) /*VGA mode*/
@@ -399,7 +402,15 @@ static void s3_virge_recalctimings(svga_t *svga)
                 }
         }
 
+        if (((svga->miscout >> 2) & 3) == 3)
+        {
+                int n = svga->seqregs[0x12] & 0x1f;
+                int r = (svga->seqregs[0x12] >> 5) & 3;
+                int m = svga->seqregs[0x13] & 0x7f;
+                double freq = (((double)m + 2) / (((double)n + 2) * (double)(1 << r))) * 14318184.0;
 
+                svga->clock = cpuclock / freq;
+        }
 }
 
 static void s3_virge_updatemapping(virge_t *virge)