ps. you can't tell the difference between SCSI and IDE (except from the connector) Be caution, SCSI uses two types of connection 68 pin & 80 pin (usually for hot swap). The adapter is about USD 20.00
By the way, the SCSI cable is also "VERY" expansive....... (5 position, 50 in is about USD 35.00)....><
The main reason why Edonkey "kills" HDD is it creates/destroy too many small temp files. This cause the the partition containing the temp file directory to fragments very quickly.
If your temp file directory situates in the your system partition, this fragmentation will cause BIG SLOW DOWN on your machine. And in extreme case, forming bad sectors.
If you really want to use edonkey client for prolong time, it is wise to have the directory set to be on a dedicated partition, or even better on a separate HDD.
Usually I run edonkey client on a dedicated linux box with a dedicated HDD just of it.