diff --git a/data/calculate b/data/calculate
index 7c5c9f2..32eda6a 100755
--- a/data/calculate
+++ b/data/calculate
@@ -38,7 +38,7 @@ variable_value()
 install_video_driver()
 {
 	ebegin "Checking video drivers"
-	case `variable_value os_x11_video_drv` in
+	case `variable_value os_install_x11_video_drv` in
 		fglrx)
 			local drv="x11-drivers/ati-drivers"
 			;;
diff --git a/pym/cl_fill_install.py b/pym/cl_fill_install.py
index 82eddd8..d13cf84 100644
--- a/pym/cl_fill_install.py
+++ b/pym/cl_fill_install.py
@@ -25,7 +25,7 @@ from os import readlink,access,R_OK
 from cl_utils import isMount,typeFile,getTupleVersion,pathJoin,isFstabMount,\
                      listDirectory, getAvailableVideo, getUUIDDict, \
                      isPkgInstalled, process, checkUtils, readLinesFile, \
-                     lspci, getPartitionSize
+                     lspci, getPartitionSize, getInstalledVideo
 from cl_distr import DistributiveRepository,PartitionDistributive
 from cl_fill import clLocale
 from operator import itemgetter
@@ -957,15 +957,14 @@ class fillVars(object, glob_attr):
     def get_os_install_x11_video_drv(self):
         """Video driver used by xorg"""
         if self.Get('os_install_root_type') == 'usb-hdd':
-            available_drivers = \
-                getAvailableVideo(prefix=self.Get('cl_chroot_path'))
+            prefix = self.Get('cl_chroot_path')
             videoVal = self.getValueFromCmdLine("calculate","video")
             videoVal = {'i915':'intel'}.get(videoVal,videoVal)
             if not isPkgInstalled('xorg-server',
                                   prefix=self.Get('cl_chroot_path')) or \
-                videoVal in available_drivers:
+                videoVal in getAvailableVideo(prefix=prefix):
                 return videoVal
-            return self.getVideoByDefault(available_drivers)
+            return self.getVideoByDefault(getInstalledVideo(prefix=prefix))
         else:
             return self.Get('os_x11_video_drv')