diff --git a/src/video/vid_s3.c b/src/video/vid_s3.c
index 33f4a217e..11321dae1 100644
--- a/src/video/vid_s3.c
+++ b/src/video/vid_s3.c
@@ -2172,6 +2172,16 @@ s3_out(uint16_t addr, uint8_t val, void *p)
 		} else if (svga->seqaddr == 0xa) {
 			svga->seqregs[svga->seqaddr] = val & 0x80;
 			return;
+		} else if (s3->chip >= S3_VISION964) {
+			if (svga->seqaddr == 0x08) {
+				svga->seqregs[svga->seqaddr] = val & 0x0f;
+				return;
+			} else if ((svga->seqaddr == 0x0d) && (svga->seqregs[0x08] == 0x06)) {
+				svga->seqregs[svga->seqaddr] = val;
+				svga->dpms = ((s3->chip >= S3_VISION964) && (svga->seqregs[0x0d] & 0xf0)) || (svga->crtc[0x56] & ((s3->chip >= S3_TRIO32) ? 0x06 : 0x20));
+				svga_recalctimings(svga);
+				return;
+			}
 		}
 		break;
 		
@@ -2376,6 +2386,11 @@ s3_out(uint16_t addr, uint8_t val, void *p)
 			}
 			break;
 
+                        case 0x56:
+                        svga->dpms = ((s3->chip >= S3_VISION964) && (svga->seqregs[0x0d] & 0xf0)) || (svga->crtc[0x56] & ((s3->chip >= S3_TRIO32) ? 0x06 : 0x20));
+                        old = ~val; /* force recalc */
+                        break;
+
 			case 0x67:
 			if (s3->chip >= S3_TRIO32) {
 				switch (val >> 4)
diff --git a/src/video/vid_s3_virge.c b/src/video/vid_s3_virge.c
index bf7b64029..0752499b3 100644
--- a/src/video/vid_s3_virge.c
+++ b/src/video/vid_s3_virge.c
@@ -428,6 +428,14 @@ static void s3_virge_out(uint16_t addr, uint8_t val, void *p)
 				svga->write_bank = svga->read_bank = virge->bank << 16;
 			else
 				svga->write_bank = svga->read_bank = virge->bank << 14;
+		} else if (svga->seqaddr == 0x08) {
+			svga->seqregs[svga->seqaddr] = val & 0x0f;
+			return;
+		} else if ((svga->seqaddr == 0x0d) && (svga->seqregs[0x08] == 0x06)) {
+			svga->seqregs[svga->seqaddr] = val;
+			svga->dpms = (svga->seqregs[0x0d] & 0xf0) || (svga->crtc[0x56] & 0x06);
+			svga_recalctimings(svga);
+			return;
 		}
 		break;
                 
@@ -543,6 +551,11 @@ static void s3_virge_out(uint16_t addr, uint8_t val, void *p)
                         case 0x58: case 0x59: case 0x5a:
                         s3_virge_updatemapping(virge);
                         break;
+
+                        case 0x56:
+                        svga->dpms = (svga->seqregs[0x0d] & 0xf0) || (svga->crtc[0x56] & 0x06);
+                        old = ~val; /* force recalc */
+                        break;
                         
                         case 0x67:
                         switch (val >> 4)