Zx20 Z420 Clover UEFI NVME Boot or What worked and what didn't. Hello all, I am writing this blog to help other folks attempting to implement a nvme boot system. This is to help other folks get here and acknowledge the work by many other google bloggers I referenced and the folks doing Clover EFI. I am posting this forum because it didn't work for me and why it didn't work. First off I can say with a 85% certainty that the Z420 with v3.94 bios and a Sabrent Rocket NVME will not boot or run an OS. The modes I tried were AHCI, both EFI then AHCI (legacy), and EFI only. The boot loaders I tried were Grub, Grub2, Winload, Clover, Refindit, Win10 boot repair and several Linux lives. The problem is this early EFI implementation did not allow me to write the bios efi to overcome the lack of a nvme driver so the OS's could load after installation. I think a recompiled Duet with the proper nvme driver would work. My system is a Z420 xeon 2650 v2, 24gb ecc ddr3 1600 ram, dual 10gbe, 8x SAS raid card, nvme pcie extender, K2000 video card, kingston 5 bay hot swap, 2x8tb sata, 2x4 SAS, 3x4 sata raid0 (16tb,12tb,8tb) and 4 500gb SSD's and the 512gb nvme. The only time I see 50% cpu usage is when compressing files in 7z or Aomei backup high compression and I never cross 65% memory usage. The crystaldisk6 marks are 3400,2200 (nvme), 550/500(ssd's), 490/450 - 380/350 raid0's. (4x4tb raid0 is 680/650 but I needed the last hot swap slot more) intel irst raid with a GPT win7 os I migrated on the fastest raid working well but it cannot see the nvme yet... sata0 ssd is MBR win10 os ahci default sata1 is the test bed ssd for for new os/efi or to migrate linux partitions from new distros. sata2 is the backup win7 os for boot problems and when win10 locks files (just f9 boot select sata2 and your are back online) sata3 is GPT grub2 boot with win10 and 10 different linux distros, my fingers like linuxmint best. nvme0 (linux name), I choose drive 'S:' in win10 (win7 can't see it, all the nvme drivers I tried blue screened and I had to go back to last known good configuration, shows as unknown pci device) The setup I recommend if you try this requires 5 or 6 SD cards (ISO's) written with Rufus 3.7 in GPT EFI mode to the SD cards. (EFI allows for drivers to be added). 3 ssd's, 1 system, 1 test and 1 for emergency boot (better then recovery) The software I liked best was aomei backup, rufus 3.7, linux mint, supergrub 2.9, bootice, easyboot 2.4, diskpart, gparted, efibootmgr, grub2-update, and I tried easyuefi but it wouldn't change my bios firmware efi. Of note visualbcd, uefitool and Supergrub(again) clonzilla, macrium, minitool, hirens, bobs, gandalfs boot iso's. I used 4 ssd boot drives for multiple boots in addition to the NVMS drive. By selecting the boot disk I can select the test disk boot, windows default boot, grub boot, grub2 boot or a backup windows boot. My preferred boot sequence is sata0 grub to windows (with choices for linux partitions, supergrub clonzilla hirens10 (and more) chainload iso's) to windows boot manager with multiple windows and supergrub selections (easybcd2.4). The only draw back to the grub mbr boot loader is when sata drive's change the menu1st file has to be manually edited for the linux partition chain loads) The grub2 ssd does this by using supergrub to boot into linuxmint on the grub2 ssd and then update-grub grub-install to the grub2 ssd. (it finds the nvme os's but won't boot to them) The very few occasions I cannot get to supergrub are simply corrected by booting to any windows and bootice the grub back to the mbr (grub not grub2). Supergrub give me access to any os installed on any drive... (except my nvme on this system...) I focused on EFI installs as I felt this was the only way to get the nvme firmware operational before a os tried to load. A newer bios on a newer motherboard can have the nvme driver installed to bios if it does not already exist. My actual testing was done by creating the gpt/efi/os on the test ssd and default booting to it to confirm everything worked properly. I then cloned the test ssd to the nvme and tried various booting methods to get to the nvme os boot. None worked. grub and windows would not see it, grub2 would find and install a link in the boot menu but device not found on reboot. Windows would set a link but also device not found error. Clover with the nvme driver copied to its efi and bios drivers would see it and link to it but not boot (blank screen - ctrl/alt/del worked so stuck in early bios, i.e. bad nvme driver) Refindit would also see the os but do a reboot when they were selected. I used the sd cards mostly when testing this as I set the boot order to default to uefi sd then uefi hard drive then legacy sd then legacy hard drive for testing. I also tried efi only to confirm the results. On the Z420 there are 3 efi settings, the efi/legacy settings in advanced storage drivers (efi is efi only) and the boot options which allow uefi to be disabled or the various uefi devices to be disabled/enabled (the efi partitions, windows boot loader is the HP default). Please note I stated efi partition('s) as it was possible to set up 2 efi partitions that the bios could see and could be default selected. Important is that it is also possible to install the clover and refindit bootloaders along with the efi winloader in the same efi partition. These can be selected by hitting esc during start selecting the use efi file option and navigating to the efi loader desired... As I understand on the z420 with this early efi implementation biosv3.94 the bios will always default to the efi/microsoft/boot loader and cannot be changed. (easyuefi couldn't) I did get to a efi edit screen via clover that I think was the bios file but it required manual entry with guid's... (didn't want to risk or take the time to edit and not sure if such would stick on reboot) So in summary I have tried to provide you folks with some short cuts and tips/programs that will help if you try this. I would buy the nvme again as the 3400/2200 is just too good to pass up and the future of things to come. A quad nvme in raid0 would be the same speed as my ddr3 memory and be instant on computing... For now I just have to settle with a split windows system with the win10 folder on sata0 with the pagefile and all the folders (programs, programs(x86), and users etc) running on the nvme. Nearly as good as a boot-able nvme with only a 1-2 second boot cost from ssd. (normal windows ssd operations consume 1-2% of the ssd speed) Do not be afraid to work with this stuff as long as you have multiple ssds, the bootable sd's and good drive cloning software. If the test drive fails you can go back to the last good clone. If you you crash the system ssd you can always go back to the last good system clone. The sd's will always get you up and running to any operational os as long as you don't brick the bios. (SUPERGRUB) When in doubt do your google homework! Please note I have excluded VM testing in this application because this is a real world hardware problem that requires hardware implementation to test. Booting to a os such as robolinux with nvme support and running a VM/VHD would run perfectly fine from the nvme. I left my raids and all ssd's installed because I took great care in knowing what I was writing to and only ate one raid setup. It was the 3x4tb motherboard irst sas and linuxmint wouldn't recognize it without MDADM installed, 1 raid disk was overwritten with gpt data either by linux or windows diskmanager(and me: yes to mbr/gpt initialize too fast) It was the gpt 12tb with a 1tb win7 partition, I just cloned the raid back and was good to go. All the raids are raid0 and I always keep 100% backups on the other computers 3 or 4 deep (10gbs network), lack of drive slots prohibit running raid10 and a 4x4tb raid0 is faster than the sequential sata ssd. (z420 has ahci sata 2-6bs, 4x3gbs and 4xsas 3gbs, and I have added a 8xSAS raid card and the last pcie1x slot held a marvel raid for awhile) (note: the Sabrent Rocket 512gb had to run in the 3x8 slot and I shuffled the dual 10gbe card to the 2x4 slot still 2000MBs, 3x16 SAS card and 3x16 video card) I choose not to use EFI when it didn't work for the nvme, because I use grub and grub2 and winload to boot into 1 of 15 different OS's. Grub gives me Supergrub boot so I can always find a system to boot to after a blue screen or missing boot.