Firewire 800 & Griffin Firewave & Hard Drive Speed

[SparkyMarky84]

Hey guys, just ordered a new 2009 mac mini and have a question.

I understand that if you plug a Firewire 400 device into a Firewire 800 port then it will reduce the entire bus speed down to Firewire 400. I wanted a bit of clarification on this.

Basically the new mac mini has only one Firewire 800 port as im sure you all know.

However i want to use an external Firewire 800 harddrive with the mini, but also to use a griffin firewave. I would be doing this via chaining.

Is there any way in which i can get the hard drive to continue to operate at Firewire 800 speeds? e.g. if i connect it as such...

Mini->Hard Drive -> Firewave

Any help is much appreciated,

thanks,

Mark

 

[SparkyMarky84]

Anyone got an idea about this?

Thanks in advance for your help guys.

Mark

 

[glennk]

Anyone got an idea about this?

Thanks in advance for your help guys.

Mark

Mark, I'd assume that you'd want to put the Firewave in first and chain the hdd to it. Otherwise if you chain the Firewave to the hdd, both would be running at FW400. Just my belief. Another option, get an Firewire hub and attach both devices there.

 

[SparkyMarky84]

I dont mind which one i plug in first, as they will both be always plugged into the mini.

But if i connect them as such

Mini<-Firewave<-Hard disk, surely it will be reduced to FW400

Whereas if i connect it this way...

Mini<-Hard disk <- Firewave, then the hard disk will operate at FW800 and the firewave will operate at FW400.

Is this correct?

 

[redsteven]

I dont mind which one i plug in first, as they will both be always plugged into the mini.

But if i connect them as such

Mini<-Firewave<-Hard disk, surely it will be reduced to FW400

Whereas if i connect it this way...

Mini<-Hard disk <- Firewave, then the hard disk will operate at FW800 and the firewave will operate at FW400.

Is this correct?

i would also like this clarified

 

[TheStrudel]

As soon as you introduce a slower link - the 400 speed - that is the connection at which your bus drops to 400. So yes, if your HDD is the FW 800 bus, connect that first, then the firewave off of that. You will have to leave the hard drive on all the time, but I assume you planned on that. Glennk appears to have confused which bus was where; if you have the firewave as the last object in the link, it will not slow down anything higher up.

 

[occamsrazor]

I'm also interested to hear a definitive answer on this...

Clearly if it goes:

Mac > FW400 > DeviceB > FW800 > DeviceA

....then you're going to get FW400 speeds to the Mac. Although in theory a transfer from A to B could still be at 800... is that right?

But has anyone actually confirmed (as opposed to theorising) that if you do:

Mac > FW800 > DeviceA > FW400 > DeviceB

..that transfers between Mac and DeviceA will be at FW800 speeds? My understanding of Firewire communication being of a node-to-node nature makes me think it is indeed the case... but I haven't tried in practice.

 

[TheStrudel]

This is correct.

However,

It's worth pointing out that you've got more crosstalk going on the bus now, so there may be a slight performance hit as a result of chaining. Those devices, unlike, say, a DV deck, are not particularly finicky, so you should be fine.