DL380 G7 Raid 10 with 8 X 1TB booting to 2012 bios issue?

We have a DL380 G7 with the 410 conroller and 4 SAS 1Tb drives configured in Raid 10.

Today I installed 4 more 1 TB drives and can see them in the HP array software, with the option to add them to the exisitng array.

If I add them to the existing array, this will create a array that is 4TB vs the current 2 TB. I was hoping to make the extra space available to the existing drive and not have to reinstall anything.

We are using Hyper V with 2 2013 VM's

If I make the new array 4Tb will the machine continue to boot or do I need UEFI set in BIOS? 

Any help or links to information appreciated.

Thanks

Doug

P.S. This thread has been moved from General to ProLiant Servers (ML,DL,SL). - Hp Forum moderator