The problem is solved, unplugged the HDD and changed the bios of the SATA by disasbling a setting(Dont remember the name) and then connected the HDD and everything is working. Thanks for the help. 

Hello PC elits!

I have problem with my PC I am usually good at fixing them but this time its pretty hard. 

I have problem booting my computer with my harddrive  I get the message "ULTRA DMA mode-5 SMART Capable but disabled" at the beginning. I know that you have to go to the bios to  enable the SMART but I cant access the bios when the harddrive is plugged in. I have tried my harddrive on another computer and it works fine and I have tried another harddrive that is exactly the same model as mine and it works on my computer. I have also updated the bios and tried other memorys. I'm thinking about buying another harddrive but I am afraid that I will get the same message again maybe should change the motherboard?

The motherboard is Conroe945G-DVI and the harddrive is Seagate 1TB.

Do you have any idea how to solve this or wich part I should change?

have you tried enabling smart without the HDD connected then connecting the HDD? Also what OS are you using?

BTW I am assuming it's a SATA HDD

Its a SATA HDD and I cant find the S.M.A.R.T option if the HDD is unplugged. Before I had XP  now I have erased the HDD thinking it might solve the problem :/

Edit:  I plugged in IDE harddrive and tricked the computer to enable the S.MA.R.T for the SATA HDD. Now I get the message "ULTRA DMA mode-5 SMART Capable and status Ok." but it stops at the same place and I still cant access the bios when the SATA HDD is connected.