diff --git a/reactos/hal/halx86/mp/apic.c b/reactos/hal/halx86/mp/apic.c
index 04770bac936..02060c8ec7d 100644
--- a/reactos/hal/halx86/mp/apic.c
+++ b/reactos/hal/halx86/mp/apic.c
@@ -818,7 +818,7 @@ MpsTimerHandler(ULONG Vector, PKIRQ_TRAPFRAME Trapframe)
    MpsIRQTrapFrameToTrapFrame(Trapframe, &KernelTrapFrame);
    if (KeGetCurrentProcessorNumber() == 0)
    {
-      KeUpdateSystemTime(&KernelTrapFrame, oldIrql);
+      KeUpdateSystemTime(&KernelTrapFrame, oldIrql, 100000); // FIXME: CLOCK_INCREMENT?
    }
    else
    {