Take a look at this:
Or see here:
You may need to update the BIOS on the motherboard also.
My Maxtor 320 GB external HDD crashed. I took it out of the enclosure and put it into my PC. I retrieved the data, and reformatted the HDD. Everything is now working fine. Except...now it is listed with only 127 GBs. Why is this? Where did all my GBs go?