Asus P5KR - Manual (Page 47)

ASUS P5KR 2-23
2.5.7 AI Slot Detector
This motherboard comes with onboard LEDs that light up when the PCIE/PCI
devices are not correctly installed. This is a reminder that you should reinstall
these devices. Refer to the figure below for the location of the LEDs.
P5KR
®
P5KR Slot Detectors
DET_X16_1
DET_PCI1
DET_PCI2
DET_X16_2
DET_PCI3
DET_PCIEX1_1
The PCIEX16_1 slot (blue) is for a PCIE x16 card. The DET_X16_1 LED lights
up despite correct installation when you install a x1, x4, or x8 card to this slot.
When the LEDs light up, turn off the power before reinstalling the devices.