From c1ba150e3c5335a5bc3b2ba86ed96c980daff34f Mon Sep 17 00:00:00 2001
From: TC1995 <mariogplayer90@gmail.com>
Date: Mon, 18 Dec 2023 00:40:31 +0100
Subject: [PATCH] Oops, they actually can mix together, but not with plain
 (non-packed) chain4 stuff enabled, should fix more mode issues in the MGA
 Millennium card.

---
 src/video/vid_mga.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/video/vid_mga.c b/src/video/vid_mga.c
index cadf64bb8..69d8de0f8 100644
--- a/src/video/vid_mga.c
+++ b/src/video/vid_mga.c
@@ -946,7 +946,7 @@ mystique_recalctimings(svga_t *svga)
             }
         }
         svga->line_compare = mystique_line_compare;
-        svga->packed_chain4 = ((svga->gdcreg[5] & 0x60) == 0x00);
+        svga->packed_chain4 = !svga->chain4;
     } else {
         svga->packed_chain4 = 0;
         svga->line_compare  = NULL;