What to do my SATA drives can not be recognized

My computer configuration is: AMD K8 3000 +, ASUS K8N-VM, GeIL DDR400 512MB, Seagate Barracuda SATA 160 (ST3160812AS), the operating system is WindowsXP SP2, but I found the system hard drive was recognized as a portable hard disk and the system the taskbar has a "Safely Remove Hardware" sign, will affect the normal use? read and write speed also is very slow, the sata hard drive can not be recognized, what should I do?

In general, SATA hard drive is recognized as a portable external hard drives in Windows XP is normal, and will not affect its normal use, if the mouse point system tray "Safely Remove Hardware" sign, will see your hard disk drives, if you point "stop" button at the same time, and it will not work, so do not worry misuse affect the use, if your hard disk read and write slowly, be sure to have installed the speed drive of SATA interface.