IBM 8687 Installation Guide - Page 84

Tip: Take the time to understand these rules and to select the best slots for your adapters. Incorrect choices can result in a loss of PCI adapter performance. As extreme configuration examples, you could configure either of the following: Six 33 MHz PCI adapters, all operating at 33 MHz. Six 133 MHz PCI-X adapters, with two operating at 133 MHz (buses C and D), two at 100 MHz (bus B) and two at 66 MHz (bus A). Important: A PCI-X and a PCI adapter can be installed in slots on the same bus. However, those two adapters will both operate in PCI mode. In addition, if you have a PCI-X adapter installed, you cannot hot-add a PCI adapter to the same bus. This is because with just the PCI-X adapter installed, the bus is running in PCI-X mode, and you cannot hot-add a PCI adapter into a bus that is in PCI-X mode. Table 3-1 summarizes the supported adapter speeds. Take into account the speed reductions when there are two adapters installed in a bus, as described above. Table 3-1 Supported adapter speeds in each slot Slot Bus Width (bits) Supported adapter speed (MHz) 1 A 32 or 64 33 or 66 2 A 32 or 64 33 or 66 3 B 32 or 64 33, 66, or 100 (133 as long as no adapter is in slot 4) 4 B 32 or 64 33, 66, or 100 (133 as long as no adapter is in slot 3) 5 C 32 or 64 33, 66, 100 or 133 6 D 32 or 64 33, 66, 100 or 133 The physical location of these slots in the server is shown in Figure 3-3 on page 71. 70 IBM ^ xSeries 440 Planning and Installation Guide