On Mar 7, 2009, at 5:27 PM, Bruce Johnson wrote: >> Can you mix different speed devices on a firewire chain, 400 and 800? >> Does the whole chain fall to the slower speed or ? > > Found this online, the results of an empirical test: > > "Summary: mixing FW400 and FW800 devices only limits the speed of the > FW800 devices if the data has to travel through a device or cable > which > uses FW400, at least for well designed Firewire devices." > > <http://tinyurl.com/djonor> > > I've also seen people say very authoritatively, but entirely without > citation that mixing them pulls you down to FW400 speed.
I've got several FW external enclosures, both FW400 & FW800, all using PATA 150 HDs. I've measured the difference in speed on a G5 dual 2.3 booting and also transferring large files on both. My conclusion was that FW800 is almost the same speed as FW400, and that the limitation is the HD itself, not the bus. Perhaps a dual HD enclosure with mirrored RAID 0 HDs would increase the throughput on FW800? I have tested a dual RAID 0 FW400 and it wasn't any faster than a single HD, so it appears the speed of a FW400 bus is saturated by a single PATA 150 HD, and this would lead me to believe that the ONLY advantage to FW800 would be to use two HDs in a RAID 0 configuration. Perhaps an SATA FW800 external would be faster than PATA? --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed Low End Mac's G3-5 List, a group for those using G3, G4, and G5 desktop Macs - with a particular focus on Power Macs. The list FAQ is at http://lowendmac.com/lists/g-list.shtml and our netiquette guide is at http://www.lowendmac.com/lists/netiquette.shtml To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/g3-5-list?hl=en Low End Mac RSS feed at feed://lowendmac.com/feed.xml -~----------~----~----~----~------~----~------~--~---
