10
Technical white paper | HP Z640 Workstation
Table 3: HP Z640 I/O slot recommended load order
Load
priority
Card description
Load order (depending on slot availability)
Slot 1*
Slot 2
Slot 3
Slot 4
Slot 5
Slot 6
CPU
PCIe3 x16
PCIe3 x8
PCIe3 x16
Chipset
PCIe2 x1
PCIe2 x4
PCI
1
Riser Card
Only
2
1st Graphics or GPU
Only
3
2nd Graphics or GPU
Only
4
3rd Graphics
Only
5
4th Graphics
Only
6
NIC – 10G
4th
3rd
2nd
1st
7
Z Turbo Drive/PCIe
storage
4th
3rd
1st
2nd
8
SAS Card
3rd
x
1st
2nd
9
HP Thunderbolt™ 2
Only
10
NIC < 10G
4th
3rd
2nd
1st
11
Audio
4th
3rd
2nd
1st
12
1394b
1st
x
2nd
x
x
13
eSATA (Cable)**
2nd
3rd
4th
1st
14
Serial port(Cable)**
2nd
3rd
4th
1st
15
PCI Card
Only
* Slot 1 is not available when Riser Card is plugged in.
** No electrical connection to PCI and PCIe slots, use any free mechanical slot location.
x Card is not supported in the slot.
Additional tips
• For applications doing direct bus Peer-to-Peer transfers between cards, load the corresponding cards in slots located
behind the CPU. For instance, load cards in slots 2, 4 and 5.
• For very high bandwidth applications in dual CPU systems, select CPU models with the highest QPI frequency (9.6 GT/s).
• Make sure all I/O cards are loaded in slots that have a PCI-Express Lane Width at least as wide as the card (see Table 3).
• For predictable latencies, try disabling NUMA (Non-Uniform Memory Access) mode (BIOS setup menu -> Advanced ->
Bus Options -> NUMA = Disabled).
• For cards that are latency sensitive, load these cards in CPU slots.
• Ensure Idle Power Savings BIOS setting is set to Normal (BIOS setup menu -> Power -> OS Power Management -> Idle
Power Savings = Normal).
• Use the latest BIOS version available on hp.com.
• Check for updates in the latest performance optimization white papers (link below).
• If a configuration has both a double-wide graphics card and a Thunderbolt™ 2
3
card, move the double-wide graphics
card from slot 2 to slot 5.
