diff --git a/src/ints/int10_modes.cpp b/src/ints/int10_modes.cpp
index b8aa3cd1..2ef66b04 100644
--- a/src/ints/int10_modes.cpp
+++ b/src/ints/int10_modes.cpp
@@ -445,7 +445,7 @@ bool INT10_SetVideoMode(Bitu mode) {
 	/* Vertical Retrace End */
 	IO_Write(crtc_base,0x16);IO_Write(crtc_base+1,(CurMode->vtotal-8));
 	/* Line Compare */
-	Bitu line_compare=(mode>=256) ? 2047 : 1023;
+	Bitu line_compare=(CurMode->vtotal < 1024) ? 1023 : 2047;
 	IO_Write(crtc_base,0x18);IO_Write(crtc_base+1,line_compare&0xff);
 	overflow|=(line_compare & 0x100) >> 4;
 	max_scanline|=(line_compare & 0x200) >> 3;