Asus M3N78 Pro Win 7 64bit set to AHCI 2tb max problem SATA

[Smax_ret]

Trying to install 6tb Toshiba Drive in M3N78 Pro system
Have upgraded to Win7 64bit
Only see 6tb as 1.5tb when plugged into SATA
BIOS set to AHCI
Shows full 6TB when in USB dock even on usb 2 (I have a pcie USB 3 card installed too)
Only need for data storage not boot drive
Any simple solution or could I install a SATA controller card

 

[Calvin7]

You need a GUID partition table (GPT) format and HDD drivers that support ≥2.2TB drives.
The motherboard looks like a 2009 model with NVIDIA GeForce 8300 chipset. I don't know if HDD drivers that support ≥2.2TB drives needed for that chipset were ever made.

 

[Smax_ret]

Thanks for that. I have set it up as gpt. Maybe it is not possible on the SATA. I cannot see a BIOS update for SATA they all seen to relate to CPUs