There does not seem to be anoption to switch from uefi to legacy and when i accidentally changed it to legacy after enabling CSM the computer failed to load windows and said no o/s present or something similar.
In the BIOS on this computer the headers are:
Main; Devices; Advanced; Power; Security; Startup and Exit
Main - system summary, set time & date and language
Devices - USB setup - usb support enabled & usb legacy support enabled
ATA drive setup; video setup; audio setup; network setup; pci express config; card reader
Advanced - cpu setup
Power - After power loss - power off
Enhanced power saving mode - disabled
auto power on - wakeup on lan - enabled
wakeup alarm - disabled
Startup - Primary boot sequence
CSM - disabled
Boot Mode - UEFI Only
Boot up num-lock status - on
Exit - save & exit
discard & exit
load optimal defaults
OS optimized defaults - enabled
Security - Admin Password - not installed; power on password - not installed
set admin password; set power on password
windows uefi firmware update - enabled
require pop on system boot - yes; require pop on system restart - no
TCG Feature setup
TCG security device - firmware TPM
security chip 2.0
clear TCG security feature