6.3.2 Setting OSA parameters using OSA Advanced Facilities If you want to change the port speed or MAC address of an OSA-Express feature, you can  use the OSA Advanced Facilities. Normally, changing MAC address is required for SNA  networks. Port speed:  You can change only the port speed to OSA-Express5S/6S 1000BASE-T.  Other OSA features do not include this capability. You cannot set port speed to 1000 Mbps for OSA-Express5S/6Sress4S 1000BASE-T. If  you want to set the port speed to 1000 Mbps, you must select  Auto Negotiate . To change port speed, complete the following steps:  Setting the OSA port speed 1. Log on to the HMC, select the CPC you want to operate, and then, click  Open OSA  Advanced Facilities . 2. Select the PCHID of the OSA channel for which you need to set the card mode. Select  Card specific advanced facilities  and click  OK . 3. Select  Set card mode  and click  OK  (see Figure 6-21). Figure 6-21 Selecting Card Mode definition 136  IBM z14 Model ZR1 Configuration Setup