The S300 is a low-end software RAID controller and only supports drives up to 2TB. The H200 and H700 and newer controllers support drives larger than 2TB.
System Info: T110 II  Xenon E3-1230 V2 3.30GHZ 8GB Ram Server 2008 R2 Standard - installed to try to get this fixed, final OS will be WHS 2011 Raid 1 -  2 x Samsung Evo 840 SDD  4 x Seagate ST3000NM0033 3TB Enterprise 128MB cache - These drives only come up as 1.9TB in the Perc screen. I have the latest firmware(A06) and now the latest bios, bios is set to run as UFEI.  I want to put these 4 drives together in a raid 10 but they will not detect their full size.  All help would be appreciated.   
Perc S300 not detecting HDD size correctly