Hi there.

I've got problems trying to make my firewire devices function to their full capablility.

I have a OWC Mercury Elite Pro Al 250Gb Triple interface external hard disk (what a mouthful!) connected to my powerbook G4 1.5Ghz via a firewire 800 cable to the onboard firewire 800 slot, and it works fine, running at 800 Mb/s.

BUT, I've also got an M-Audio Projectmix which connects with a firewire 400 cable. I've just bought a PCMCIA firewire adapter so that the hard disk and the Projectmix can have their own separate bus, but when I plug the Projectmix in the speed of the Hard disk connection drops to 400Mb/s.

I can't understand why, when they're connected on different buses.

(The whole reason why I bought the PCMCIA Firewire card was to get around this problem!)

Please help!!

Thanks.

First time I see this!

Which PCMCIA card is it? OS X flavour?

The PCMCIA card doesn't have a manufacturer name on it! It's a Firewire/USB cardbus adaprer and it's compatible with OS X and it has drivers for OS X.

Where does it come from?

It's this one:

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?Vie...AMEWN%3AIT&rd=1

I bought it off ebay from a seller called usb4sale. I have e-mailed the seller to see if there's any tech support for this card, but he hasn't replied yet.

check in system profiler to see if there is any more specific information on the card, then try to google that and see what you come up with

There's no information about the card in system profiler. It just says:

FireWire Bus:

Maximum Speed: Up to 400 Mb/sec

I've just noticed that in the top window of the profiler in the firewire tab, the firewire card's FireWire Bus sits above the Built-in FireWire bus. Does this mean it's higher in priority? Is there any way to change them around?

Just inserting the card makes the speed of the built-in bus drop to 400Mb/s regardless of whether any firewire devices are plugged into it.

I'm not sure at all if the order in the profiler is relevant as for a priority order… I doubt it.

If inserting the card only makes the speed dive down low to crawl, I think you have a suspect It's stupid it's so difficult to know exactly what is inside it as it's not this way we'll know if it can be firmware upgraded…

There must be some Terminal commands to list peripherals but it's beyond my humble knowledge…

On the tricks side there may be some things to try like find which PCMCIA card has the same black plastic part and see if it has updaters and try them but it trial/error/eventually destruction… Now we are sure of one thing, it interferes in a way it shouldn't, so it is not fully compatible with your laptop/OS.