IBM 440 manual Slot Bus Width bits Supported adapter speed MHz

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