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TyleRomeo
Dec 30, 2006, 08:52 AM
The 64 bit 33MHZ PCI slots on a G4 are running at 133MBps correct? Also I want to know if all 4 of them are running fully inpendent from each other? So if I have a RAID card in there I can get the full 133MBps and will not be robbed of speed if I have a neighboring Firewire 800 or SATA RAID next to it.



mklos
Dec 31, 2006, 06:51 PM
All 4 slots share the same bus to the system controller. So its a shared bus. They all have their own bus to the main bus that goes to the system controller, but once its on that main bus its all shared. I know it sounds confusing doesn't it.

Here are a couple of links to help you:

http://developer.apple.com/documentation/Hardware/Developer_Notes/Macintosh_CPUs-G4/PowerMacG4/2Architecture/chapter_3_section_2.html#//apple_ref/doc/uid/TP40000928-TP30000304-TPXREF102


http://developer.apple.com/documentation/Hardware/Developer_Notes/Macintosh_CPUs-G4/PowerMacG4/4Expansion/chapter_5_section_3.html#//apple_ref/doc/uid/TP40000928-TP30000306-TPXREF108

TyleRomeo
Dec 31, 2006, 09:39 PM
Hmm, I took a look at the links, but I'm still a bit confused. Let me see if I get this right. The max burst for each PCI slot is 133MBps. So all 4 of them would give me 533MBps. But all of this just depends on how much else I have going in thru the system controller and that depends on my crappy 167MHZ bus that translates to 1.3GBps transfer speed for all info for my computer. Am I getting close?

All 4 slots share the same bus to the system controller. So its a shared bus. They all have their own bus to the main bus that goes to the system controller, but once its on that main bus its all shared. I know it sounds confusing doesn't it.

Here are a couple of links to help you:

http://developer.apple.com/documentation/Hardware/Developer_Notes/Macintosh_CPUs-G4/PowerMacG4/2Architecture/chapter_3_section_2.html#//apple_ref/doc/uid/TP40000928-TP30000304-TPXREF102


http://developer.apple.com/documentation/Hardware/Developer_Notes/Macintosh_CPUs-G4/PowerMacG4/4Expansion/chapter_5_section_3.html#//apple_ref/doc/uid/TP40000928-TP30000306-TPXREF108