This is a Dell Poweredge T410 which is about 5 years old now and is running SBS2008. It has 6 hot swap drive bays on the front panel. It came supplied with 2 x 500g drives plugged into the left hand bays on the top row in a Raid 1 configuration. The raid controller has two channels. I always assumed that one drive would be on each channel, but it turns out that they are both on the same Channel. I also found that of the six bays, 4 of them are wired to one channel whilst only 2 are wired to the other channel.
I'm about to replace one of the disks today, and i'm wondering if there is any performance advantage to be had if I put the replacement disk on the other channel?