[G4] Re: SCSI card for G4

[Eric Smith]

Technophobic_Tom at comcast.net wrote:
> Mel wrote:
> 
>>  Technophobic Tom wrote:
>>
>>>  Eric wrote:
>>>>
>>>>  [ATTO] recommended the two cards that are described here:
>>>>  http://www.mactech.com/articles/mactech/Vol.22/22.04/ATTOReview/index.html 
>>>>
>>>
>>>  I notice that these are PCI-X cards.
>>>  Will they work in the G4 PCI slots?
>>
>>  Didn't the text in the link state that
>>  they were used under OS X in a Mac?
> 
> Yes...a G5 which might have PCI, PCI-X, or PCIe. And that means what wrt 
> PCI-X cards in a G4 PCI machine? I gather that the PCI-X 2.0 standard 
> provides for PCI cards on PCI-X busses but my questions targets the 
> compatibility of PCI-X cards on the slower PCI busses. One would think 
> that with the added pins on a PCI-X card, it wouldn't even fit in a PCI 
> slot. I'm in the dark here. :-/

Hi Tom,

 From http://en.wikipedia.org/wiki/PCI-X :

"PCI-X is generally backward-compatible with most cards based on
the PCI 2.x or later standard, meaning that, a PCI-X card can be
installed in a PCI slot, provided it has the correct voltage keying
for the slot and (if inserting into a 32-bit slot) nothing obstructs
the overhanging part of the edge connector."

(On the other hand, PCIe is not compatible with either PCI or PCI-X.
But only the dual-core G5s - not dual-processor - have PCIe.)

Eric S.