Fujitsu PRIMERGY RX300 S6 Operating Manual page 16

Features
Fujitsu Technology Solutions offers a unique patented solution to deliver the
highest possible bandwidth with four PCIe Gen2 x8 slots: two of the four PCIe
Gen2 x4 slots can each be used as PCIe Gen2 x8 slots if the neighboring slot
is free.
Figure 1: Slots for expansion cards - Basic Configuration
Seq. No.
1
2
3
4
5
6
7
Table 1: Slots for expansion cards
16
Slot no. Features
1 PCI express x4 (SAS/SATA RAID controller)
2 PCI express x4
3 PCI express x4 (x8 only when slot 2 remains
empty)
4 PCI express x4
5 PCI express x4 (x8 only when slot 4 remains
empty)
6 PCI express x8
7 PCI express x8
Operating manual
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RX
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300 S6