Archived from groups: comp.sys.ibm.pc.hardware.chips (
More info?)
daytripper <day_trippr@removeyahoo.com> wrote:
> On Wed, 13 Jul 2005 18:10:57 -0400, Yousuf Khan <bbbl67@ezrs.com> wrote:
> >Nate Edel wrote:
> >> In practice, I can give one datapoint - which is that Intel ships a
> >> motherboard riser with two PCI-E 4x slots with 8x connectors - and that
> >> 8x cards (Mellanox IB adaptors) do work in those 4x slots (I don't
> >
> >Are the x4 & x8 connectors physically the same? I think x8 and x16
> >usually are, right?
>
> The spec provides for unique x1, x4, x8 and x16 connectors, fwiw.
The 4X slots are considerably shorter. Probably half?
> I suspect designers tend to use x4 connectors for x1 slots, x8 for x4
> slots, and x16 for x8 slots, just to provide greater flexibility (if no
> higher performance) wrt add-in cards.
We had two vendors' 2U PCI-E boxes we were evaluating; the stock Intel one
had 2 4x slots with 8x connectors. The other vendor had a regular 4x slot
in the first version of the riser we got, then an actual 8x slot.
--
Nate Edel http://www.cubiclehermit.com/
"I do have a cause, though. It is Obscenity. I'm for it." - Tom Lehrer