replace interface cable w/new drive?

I have a G4/350 Sawtooth. I've just replaced the original 10gb western
digital hard drive with a 120gb Seagate drive. (There's also an 80gb
Western digital Drive installed).

After installing (everything seems to work well) I noticed that
Seagate's instructions recommend replacing the ATA (or is it IDE?) cable
that connects the drives to the motherboard with the cable supplied in
their box "because some older drive cables cannot support your new
drive's higher data transfer rates."

Is this meaningful in my case? Is it worth the trouble for me to go back
in and replace the cable?

Thanks in advance for any help.