connecting hdd to imac with firewire 800?

[MuGeN]

daft question i'm sure, but after realising i can't connect to my imac with the same cable as i used on my macbook (400), i found the box and home and found the 800 cable...

plugged it into my imac but the hdd doesn't spring to life... i've tried the cable in both of the FW slots but it just won't initialise (i can hear that its powered up but the lights don't come on and it doesn't mount to the desktop...)

any ideas? am i being a bit daft?

EDIT its a 500GB My Book Studio by the way

 

[MuGeN]

just connected with the usb cable and its fine

with firewire 800 do you just connect from one of the sockets on the hdd to your mac with one cable? i'm a bit confused as to why there are 2 identical firewire sockets on the drive?

 

[MuGeN]

no idea, i've tried both FW ports to no avail... this drive works fine with my macbook over FW400 too so its a bit of a mystery...