IBM 74Y4064 Handbook page 152

I/O bus architecture
PCI Express (PCIe) Base and Card Electromechanical (CEM) 2.0 x8 PCIe bus interface
Slot requirement
For more information about slot priorities, maximums, and placement rules, see PCIe adapter
placement rules and slot priorities (http://www.ibm.com/support/knowledgecenter/POWER9/
p9eab/p9eab_mtm_pciplacement.htm) and select the system that you are working on.
Voltage
3.3 V
Form factor
Short, low-profile with standard size bracket
FC compatibility
2, 4, 8 Gigabit
Cables
Cables are the responsibility of the customer. Use multimode fibre optic cables with short-wave
lasers that adhere to the following specifications:
v OM3: Multimode 50/125 micron fibre, 2000 MHz x km bandwidth
v OM2: Multimode 50/125 micron fibre, 500 MHz x km bandwidth
v OM1: Multimode 62.5/125 micron fibre, 200 MHz x km bandwidth
Because core sizes are different, OM1 cables can only be connected to other OM1 cables. For best
results, OM2 cables should not be connected to OM3 cables. However, if an OM2 cable is
connected to an OM3 cable, the characteristics of the OM2 cable apply to the entire length of the
cables.
The following table shows the supported distances for the three different cable types at the three
different link speeds.
Table 39. Supported cable distances by link speed
Cable type
OM3
OM2
OM1
Adapter LED
Green and yellow LEDs can be seen through openings in the adapter mounting bracket. Green indicates
firmware operation and yellow signifies port activity. Table 40 summarizes the link rate conditions. There
is a 1-second pause when the LED is off between each group of fast flashes (2, 3, or 4). Observe the LED
sequence for several seconds to be sure that you have correctly identified the state.
Table 40. Normal LED states
Green LED
Slow flash
On
On
On
Power-on self test (POST) conditions and results are summarized in Table 41 on page 137. These states
can be used to identify abnormal states or problems. Follow the action to be taken for each condition.
136
Managing PCIe adapters
2.125 Gbps
0.5 m - 500 m
0.5 m - 300 m
0.5 m - 150 m
Yellow LED
Off
2 fast flashes
3 fast flashes
4 fast flashes
4.25 Gbps
0.5 m - 380 m
0.5 m -150 m
0.5 m - 70 m
State
Normal, link inactive or not started
2 Gbps link rate - normal, link active
4 Gbps link rate - normal, link active
8 Gbps link rate - normal, link active
8.5 Gbps
0.5 m - 150 m
0.5 m - 50 m
0.5 m - 21 m