UEFI


If you happen to get a nice laptop with a powerful graphics card, such as polish HYPERBOOK SL502VR [1], it is highly probable that you will use UEFI boot mode. In that case you need to use SCFB [2] driver instead of VESA. Use the xf86-video-scfb package to get Xorg running.

Hybrid Graphics at first used MUX device that did a LCD connect to a selected video card on boot. Nowadays both cards use common Video Framebuffer [3] to draw over a screen. The simple video card (Intel in my case) is always active, while the more powerful and power consuming video card is started on-demand (nVidia in my case). This however requires a dedicated DMA BUF implementation, which is not yet available on FreeBSD, so none of the cards can see any monitor connected, resulting in “No Screens Found Error” from Xorg.

I have already reported a bug/feature request to nVidia. Also developers of FreeBSD are working on the Hybrid Graphics implementation.

[1] http://sklep.hyperbook.pl/hyperbook-sl502-vr-p651rp6g-gtx-1060-p-25965.html
[2] https://wiki.freebsd.org/Graphics/SCFB
[3] https://en.wikipedia.org/wiki/Framebuffer

UEFI


If you want to build your own disk array, let’s say RAID, on your computer to increase disk space and efficiency, you should know about few important things in general:

  • You can consider MBR and x86 obsolete. New way is GPT, UEFI, AMD64.
  • Large RAID arrays (over 2TB) will not work with older hardware and OS (except FreeBSD) due to architecture limitations.
  • To use large RAID volumes you must use GPT partition scheme. MBR will not do the job.
  • Some systems can use GPT only with UEFI BIOS (i.e. Windows works with GPT only via UEFI). You may be forced to buy new motherboard.
  • UEFI and GPT is totally different way of bootstrap so you can forget what you know about BIOS and MBR here.
  • Hard Drives have hidden corruption-fix mechanisms in firmware that will make your RAID array fail to operate. For RAID choose dedicated drives such as WD RED (not Green, not Black, not Blue).

In order to use GPT and UEFI I have replaced my nice ASUS M4A88TD-V EVO/USB3 motherboard with M5A97 R2.0 only because M4 series did not support UEFI. New BIOS is totally different, but I am not really sure if replacing the hardware was mandatory..

Summing up, if you want to use large RAID volumes make sure first that you can use GPT and UEFI BIOS is present on your AMD64 hardware. If not, still you can use the FreeBSD as it knows how to bypass some limitations. Also remember to use dedicated HDD for RAID operations.