HP DL380 G5 Predictive failure of a new drive
Solution 1:
This is a Smart Array P400 controller, so the machine is of the ProLiant G5-era, placing it as more than three years-old and out of standard warranty.
Before going with another replacement drive, I'd suggest updating the firmware of your RAID controller, since misreporting is a symptom of some of the early firmware revisions (changelog).
You did not specify your operating system version, But the Linux firmware is here and the Windows firmware is here. You will need a reboot.
If you're up-to-date on the firmware already, a power-off and power-on cycle (remove the power cables for a few minutes) may work to get things up again.
In general, firmware on HP ProLiant gear is key, so if you can spare the time (30 minutes), run the full bootable Firmware update DVD to bring BIOS, controllers, disks, ILO2, etc. to a more current revision level.
Solution 2:
It could just be bad luck but I have seen firmware issues on HP kit misdiagnose prefailed hardware before. What I suggest you should do is upgrade EVERY bit of firmware in the whole box, they make that easy now with those Proliant Pack things, just boot from the CD or .iso-over-iLO and it just runs, takes say 10-15 minutes and you then know the box is at a supportable level. Only then will you know for sure whether it's just a dead disk or not, that ok?