Index: /trunk/src/VBox/Additions/x11/vboxvideo/vboxvideo.c
===================================================================
--- /trunk/src/VBox/Additions/x11/vboxvideo/vboxvideo.c	(revision 55235)
+++ /trunk/src/VBox/Additions/x11/vboxvideo/vboxvideo.c	(revision 55236)
@@ -863,6 +863,6 @@
      * took the first valid values set to these two as maxima over the
      * server lifetime. */
-    pScrn->virtualX = 32000;
-    pScrn->virtualY = 32000;
+    pScrn->virtualX = VBOX_VIDEO_MAX_VIRTUAL;
+    pScrn->virtualY = VBOX_VIDEO_MAX_VIRTUAL;
 #else
     /* We don't validate with xf86ValidateModes and xf86PruneModes as we
@@ -1089,5 +1089,5 @@
     /* Set a sane minimum and maximum mode size to match what the hardware
      * supports. */
-    xf86CrtcSetSizeRange(pScrn, 64, 64, 16384, 16384);
+    xf86CrtcSetSizeRange(pScrn, VBOX_VIDEO_MIN_SIZE, VBOX_VIDEO_MIN_SIZE, VBOX_VIDEO_MAX_VIRTUAL, VBOX_VIDEO_MAX_VIRTUAL);
 
     /* Now create our initial CRTC/output configuration. */
Index: /trunk/src/VBox/Additions/x11/vboxvideo/vboxvideo.h
===================================================================
--- /trunk/src/VBox/Additions/x11/vboxvideo/vboxvideo.h	(revision 55235)
+++ /trunk/src/VBox/Additions/x11/vboxvideo/vboxvideo.h	(revision 55236)
@@ -129,4 +129,7 @@
 #define VBOX_DRI_DRIVER_NAME  "vboxvideo"  /* For starters. */
 #define VBOX_MAX_DRAWABLES    256          /* At random. */
+
+#define VBOX_VIDEO_MIN_SIZE    64
+#define VBOX_VIDEO_MAX_VIRTUAL (INT16_MAX - 1)
 
 #define VBOXPTR(p) ((VBOXPtr)((p)->driverPrivate))