The drive's current firmware package version (PH0G2D.CCD4.JQ019Y.CC49) is consistent with Seagate's official CC49 Pharaoh update:
http://www.users.on.net/~fzabkar/HDD/PH-CC49.TXTCode:
#PHARAOH 2 HEAD
ST332041?AS;PH0G2D.CCD3.AA????.CC3?.D2??;PHCC492H.LOD;PH0G2D.CCD4.JQ019Y.CC49.D289
ST332041?AS;PH0G2D.CCD3.BZ????.CC3?.D2??;PHCC492H.LOD;PH0G2D.CCD4.JQ019Y.CC49.D289
ST332041?AS;PH0G2D.CCD3.CL????.CC3?.D2??;PHCC492H.LOD;PH0G2D.CCD4.JQ019Y.CC49.D289
ST332041?AS;PH0G2D.CCD3.CN????.CC3?.D2??;PHCC492H.LOD;PH0G2D.CCD4.JQ019Y.CC49.D289
ST332041?AS;PH0G2D.CCD3.CT????.CC3?.D2??;PHCC492H.LOD;PH0G2D.CCD4.JQ019Y.CC49.D289
ST332041?AS;PH0G2D.CCD3.FV????.CC3?.D2??;PHCC492H.LOD;PH0G2D.CCD4.JQ019Y.CC49.D289
ST332041?AS;PH0G2D.CCD4.AA????.CC4?.D2??;PHCC492H.LOD;PH0G2D.CCD4.JQ019Y.CC49.D289
ST332041?AS;PH0G2D.CCD4.BZ????.CC4?.D2??;PHCC492H.LOD;PH0G2D.CCD4.JQ019Y.CC49.D289
ST332041?AS;PH0G2D.CCD4.CL????.CC4?.D2??;PHCC492H.LOD;PH0G2D.CCD4.JQ019Y.CC49.D289
ST332041?AS;PH0G2D.CCD4.CN????.CC4?.D2??;PHCC492H.LOD;PH0G2D.CCD4.JQ019Y.CC49.D289
ST332041?AS;PH0G2D.CCD4.CR????.CC4?.D2??;PHCC492H.LOD;PH0G2D.CCD4.JQ019Y.CC49.D289
ST332041?AS;PH0G2D.CCD4.CT????.CC4?.D2??;PHCC492H.LOD;PH0G2D.CCD4.JQ019Y.CC49.D289
ST332041?AS;PH0G2D.CCD4.DP????.CC4?.D2??;PHCC492H.LOD;PH0G2D.CCD4.JQ019Y.CC49.D289
ST332041?AS;PH0G2D.CCD4.EB????.CC4?.D2??;PHCC492H.LOD;PH0G2D.CCD4.JQ019Y.CC49.D289
ST332041?AS;PH0G2D.CCD4.GZ0?9Y.CC??.D2??;PHCC492H.LOD;PH0G2D.CCD4.JQ019Y.CC49.D289
ST332041?AS;PH0G2D.CCD6.CR????.CC6?.D2??;PHCC492H.LOD;PH0G2D.CCD4.JQ019Y.CC49.D289
ST332041?AS;PH0G2D.CCD7.BZ????.CC7?.D2??;PHCC492H.LOD;PH0G2D.CCD4.JQ019Y.CC49.D289
ST332041?AS;PH0G2D.CCD7.DQ????.CC7?.D2??;PHCC492H.LOD;PH0G2D.CCD4.JQ019Y.CC49.D289
Therefore it appears that the user has applied the retail CC49 update to OEM KC45 firmware. I'm not sure whether that was wise.
At present the drive is reporting a reduced capacity of 578258352 sectors which corresponds to 296GB (= 276GiB). This would suggest that a HPA is in force. If so, then tools such as HDAT2, MHDD or SeaTools should be able to remove the HPA and restore the drive's full capacity.