A quick search of those X-option numbers at Store.Sun.Com
shows the first disk to be an Ultra3 LVD SCSI drive,
and the second one to be an Ultra320 non-LVD disk.
... vastly different prices, by the way.
If I were to spend more time searching this, I'd think about ....
....... logging into Sunsolve, then go to the SSH and use its search function
to find out what systems or storage peripherals they're actually qualified for.
The login version of the SSH lets you see more details.
like I said before, they are the same exact drive...
check the web pages that I have already listed...
X5263A* 390-0275* Seagate ST373207LC (73.4GB - 10000 RPM Ultra-320), RoHS:Y
X5264A* 390-0275* Seagate ST373207LC (73.4GB - 10000 RPM Ultra-320), RoHS:Y
how can these be different?
haroldkarl