Security of Qubes OS on PC w/ motherboard w/ outdated firmware

Hi, is security severely compromised on a PC with outdated firmware (last UEFI update 2012/13) with no available update and no coreboot images to flash externally?
I have Qubes OS installed on a PC w/ ASUS motherboard (noname PC, something I bought cheap on Amazon 3 yrs ago), everything works great, just would like to know how secure is the system, because of the facts above.
Am thinking to switch to NItroPC (Nitrokey), but if there is no need to, would rather save 1000+ $.
Thanks in advance.

It really depends on your threat model and security on the home network.
Good firewall? Separate WiFi subnet? Not a great deal to protect on the QubesOS install, by which I mean that you don’t risk your freedom nor financial ruin if you get hacked? If you answered 3xYES, you’re good to go.