Changing the controller mode is not a good idea, especially if the OP actually wants the controller in something other than IDE mode.It's either set to AHCI or RAID in the controller settings in BIOS, both of which can cause the above as drivers are needed, change it to IDE (or AHCI first if it is set to RAID) and try again.
What HDD and mobo are you using? Which SATA controller is the drive connected to?hardrive is detected in bios , what im doing wrong ?
Changing the controller mode is not a good idea, especially if the OP actually wants the controller in something other than IDE mode.
If Windows was on the drive before then 7 won't see it on some occasions depending on the drive state. Something to do with MBR/Partition tables.
Just wipe the drive clean using a Windows XP CD to boot with but don't run through XP setup - the drive should show up in 7 setup afterwards allowing you to create a new partition.
mob has sata 3