SATA supports hot plugging. That means data drives can be plugged
and unplugged while the system is running. Full support for this
was not available when SATA was introducted. With some of the
latest SATA hardware (supporting 3Gbit/sec on the cable), hot
plugging is now properly supported in the driver.

I've read in these groups, that you cannot "remove" your boot drive,
as the OS will not let you. If you look around, you may find a
recipe for removing the "Safely Remove" icon, if you don't want
it. It exists, because the driver has indicated to the OS, that
the device supports hot plugging.

To remove a SATA drive from the system, clicking "Safely Remove"
ensures all data is flushed to the platters, before the user
unplugs the drive. Otherwise, some of the data may still be in
a cache somewhere, which would leave the disk in a slightly
corrupted state.

This article explains some settings for the Notification area.

"Description of Notification Area Settings"
http://support.microsoft.com/default.aspx?scid=kb;en-us;279771

   Paul

David:
Because SATA HDDs are generally considered "hot-swappable" devices, a number
of motherboards treat that type of drive as a removable device in the sense
that the Safely Remove Hardware icon will appear in the Notification Area
(a/k/a the Systray) on the Taskbar area similar to the way the SRH icon
would appear for example if a USB external HDD or flash drive was connected.
I assume that's what you're referring to when you say your motherboard "sees
it as a removeable device...". In any event, you can safely ignore the icon;
there's no need to access it for any reason since it has no effect on the
performance of the SATA HDD.

I'm assuming in all this that your SATA HDD is performing without problems
and that you're merely concerned with the display of the SRH icon.

I'm further assuming that your 250 GB SATA HDD is a SATA-II model and that
your ASUS motherboard supports SATA-II capability, i.e., including the
"hot-swappable" aspect so that you use the drive in that fashion (similar to
a USB external device for example) if you want to.
Anna