99% your 810 do not support this 80 GB but but
u can purchase PCI IDE card which cost is around Rs. 1250/- with 1 year warranty
and in BIOS u have to silect 1st Boot device SCSI.!!
and this card support 160GB or more than that and in this card u can get 2 IDE Access so then in your system total 4 IDE Access..!!
Ok
if it is affordable then Go for it..!! and Enjoy...!!