diff --git a/rtl/inc/video.inc b/rtl/inc/video.inc
index b2eb712b8f..c2083a46a6 100644
--- a/rtl/inc/video.inc
+++ b/rtl/inc/video.inc
@@ -79,7 +79,7 @@ end;
 Procedure AssignVideoBuf (OldCols, OldRows : Word);
 
 Var NewVideoBuf,NewOldVideoBuf : PVideoBuf;
-    S,I,C,R,NewVideoBufSize : Integer;
+    S,I,C,R,NewVideoBufSize : longint;
 
 begin
   S:=SizeOf(TVideoCell);
diff --git a/rtl/win32/video.pp b/rtl/win32/video.pp
index 9b1b9df98f..58a8e7db84 100644
--- a/rtl/win32/video.pp
+++ b/rtl/win32/video.pp
@@ -414,7 +414,7 @@ begin
       SysVMD[SysVideoModeCount-1].Col:=dwMaximumWindowSize.X;
       SysVMD[SysVideoModeCount-1].Row:=dwMaximumWindowSize.Y;
       SysVMD[SysVideoModeCount-1].Color:=true;
-      OrigScreenSize := dwMaximumWindowSize.X * dwMaximumWindowSize.Y * SizeOf (Char_Info);
+      OrigScreenSize := max(dwMaximumWindowSize.X,dwSize.X) * max(dwMaximumWindowSize.Y,dwSize.Y) * SizeOf (Char_Info);
     end;
   GetMem (OrigScreen, OrigScreenSize);
   with C do