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From: Roland Dreier <rdreier@cisco.com>
To: ddutile@redhat.com
Cc: Krzysztof Halasa <khc@pm.waw.pl>, Stefan Assmann <sassmann@redhat.com>,
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       Jesse Barnes <jbarnes@virtuousgeek.org>, kaneshige.kenji@jp.fujitsu.com,
       matthew@wil.cx
Subject: Re: GT/s vs Gbps for PCIe bus speed
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Date: Thu, 15 Oct 2009 00:40:46 -0700
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 > Yeah, the std nomenclature is PCI-e not PCI-E.

To be pedantic: "PCIe" without the hyphen is correct, cf
http://www.pcisig.com/specifications/pciexpress/ (the web page, not any
member-only specs) -- "PCIe" is used many times there.

 > Again, trying to generate output that relates
 > to what devices are spec to run at: 2.5GHz or 5.0GHz links.

But the spec does not talk about rates in GHz but rather GT/s (since
PCIe is not clocked but rather uses a recovered embedded clock).
Matching the terminology of the PCIe spec by using GT/s really seems
best in terms of clarity, and describes the situation most exactly,
since by using GT/s one also sidesteps the issue of having the data rate
depend on the link width.

 - R.