Caution
: If at all possible, avoid the user of a riser card.
Although PCI riser cards are commonly used, they will
generally violate PCI specifications for the length of signal
traces. A riser card may also introduce impedance
discontinuities and signal degradation between the mother
board, riser card, and network interface card. If you
observe PCI-communication errors when using a riser
card, see if the problem persists when you plug the
Myrinet/PCI-X NIC directly into the PCI slot. A higher
quality riser card -- one whose traces match the impedance
of signals on the mother board and NIC -- may also solve
the problem.
Also, it is important that a 64-bit riser card be used in a
64-bit PCI slot, and likewise a 32-bit riser card should be
used in a 32-bit PCI slot. Otherwise, the Myrinet/PCI-X
NIC will not be correctly detected and/or serious
performance irregularities will result.
Note: Inserting a PCI-X NIC into a 64-bit / 66MHz PCI slot
As previously mentioned, the Myrinet/PCI-X NICs support both PCI-X and PCI
protocols, and can be used in any 3.3V PCI slot. Thus, it is possible to insert a
Myrinet/PCI-X NIC into a PCI slot running at 64-bit/66MHz. However, if this is
done, the 64-bit NIC will run at reduced speed (66MHz).
Step 3: Secure the NIC in place with a locking screw (if applicable),
replace the exterior cover of the host, and attach the cable (Fiber)
between the NIC and the switch (as detailed on pages 3-4 of the
document “Guide to Myrinet-2000 Switches and Switch Networks,”
available at
http://www.myri.com/myrinet/m3switch/guide/index.html)
.
Please follow the instructions in the “Guide to Myrinet-2000 Switches and Switch
Networks” when connecting/disconnecting cables to/from cards and switches.
Step 4: Power on the host and check that the NIC is detected by the host
operating system.
Depending upon the operating system running on the host, this detection
mechanism varies, as detailed below. After the Myrinet PCI-X/Host NIC has
been correctly detected, refer to the
Software Download
section of the
Software
and Customer Support
webpage (
http://www.myri.com/scs/#downloads
) for
details of the recommended software and installation instructions.
Troubleshooting information can be found in the Troubleshooting section of the
Myrinet FAQ
(
http://www.myri.com/scs/FAQ
) as well as the document "Myrinet
Installation and Troubleshooting Guide".
© 2005 Myricom, Inc. DRAFT
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