diff --git a/devices/video/atimach64gx.cpp b/devices/video/atimach64gx.cpp
index 3f0c7b7..8e7e0df 100644
--- a/devices/video/atimach64gx.cpp
+++ b/devices/video/atimach64gx.cpp
@@ -25,7 +25,6 @@ along with this program.  If not, see <https://www.gnu.org/licenses/>.
  */
 
 #include <core/bitops.h>
-#include <core/timermanager.h>
 #include <devices/deviceregistry.h>
 #include <devices/video/atimach64defs.h>
 #include <devices/video/atimach64gx.h>
@@ -307,17 +306,8 @@ void AtiMach64Gx::enable_crtc_internal()
         ABORT_F("%s: unsupported pixel depth %d", this->name.c_str(), this->pixel_depth);
     }
 
-    if (this->refresh_task_id) {
-        TimerManager::get_instance()->cancel_timer(this->refresh_task_id);
-    }
-
-    uint64_t refresh_interval = static_cast<uint64_t>(1.0f / this->refresh_rate * NS_PER_SEC + 0.5);
-    this->refresh_task_id = TimerManager::get_instance()->add_cyclic_timer(
-        refresh_interval,
-        [this]() {
-            this->update_screen();
-        }
-    );
+    this->stop_refresh_task();
+    this->start_refresh_task();
 
     this->crtc_on = true;