diff --git a/src/Makefile.mingw b/src/Makefile.mingw
index 5adf466e6..e6651d08b 100644
--- a/src/Makefile.mingw
+++ b/src/Makefile.mingw
@@ -148,6 +148,9 @@ else
 DBFLAGS = 
 endif
 
+ifeq ($(DEV_BRANCH), y)
+CFLAGS		+= -DDEV_BRANCH
+endif
 
 ifeq ($(WALTJE), y)
 OPENDIR = win_opendir.o
diff --git a/src/VIDEO/vid_nv_riva128.c b/src/VIDEO/vid_nv_riva128.c
index 1bb638e50..d43b9e114 100644
--- a/src/VIDEO/vid_nv_riva128.c
+++ b/src/VIDEO/vid_nv_riva128.c
@@ -2200,7 +2200,7 @@ void rivatnt_pgraph_ctx_switch(void *p)
 			ret = (riva128->i2c.sda << 3) | (riva128->i2c.scl << 2);
 			break;
 		case 0x28:
-			ret = svga->crtc[0x28] & 3;
+			ret = svga->crtc[0x28] & 0x3f;
 			break;
 		default:
 			ret = svga->crtc[svga->crtcreg];