- Pull CMOS battery and disconnect you PSU from power (for at least 10 minutes).
- Unplug ALL PCI-e/PCI devices you are using, and plug only GPU (PCI [NON-express], with DirectX 8+ support if available)
- Check if it POSTs.
- If it doesn’t, use BIOS Flashback to downgrade to 470x version and check again
- If this doesn’t work, try to populate all memory DIMM slots/test each DIMM (for recommend occupation check manual), switch DRAM modules for something smaller capacity (1-4GB) if you own any
- If that doesn’t work, change CPU (for know good), and repeat all above steps.
- When everything above fails, you have two options :
A) Give up, board is dead.
B) Try to desolder BIOS chip to check if it’s valid
Hi Guys, how do I create a custom version of this mod?, I need a specific situation that the bifurcation version doesn’t suit me, I’m using my SBx79 with VMWARE Esxi 8 and a tesla p4 and a tesla p40, the P40 because it is 24gb it needs 4g decoding, but I don’t have it in the version without bifurcation, the version with bifurcation does not work correctly vt-d and I can’t passthrough the cards in the vms only with the version without bifurcation that but without 4g decoding the n da post plate with the p40
Config:
E5-2650v2 - (i will update to 2697 soom)
Tesla P4 8gb
Tesla P40 24gb
Nvidia GF 8400 - Just For Video
RAM 32GB
OS´s
Proxmox 7x
Vmware Sphere 8x
P4 Passthrough ok on 4701 no bifurcation but no post on P40 8Beep Warning
P4 and P40 Working on 47/4801 bifucation with 4g decoding On - But V-td not workin propely and passthrough on Proxmox or Vmware show error 43 or error 10
it seems to be a bug because when I activate only a single option in the version without a bifucation it works without any problem, so I sacrifice the nvme but I would like to be able to use the 4G decoding to activate the P40 as well and not have to mount it another kit for my server to use the P40
HELP 
EDIT: after spending a few minutes/hours looking here in the forum I found the programs that edit the bios to show and hide options, and also activate what I need without needing them to appear, I want to thank everyone who contributes to this community because without this community it would never be possible to put my personal project to work…
thank you all
EDIT2: 4g Decoding not working properly on SBx79 i cant use p40 on this motherboard.
[ ]´s
NeO
After a bit of trial and error, it worked.
I changed the 8x port to 4x + 4x (which is the bottom slot on the motherboard). And then put each M.2. ssd on slot 1 and 2 of the card.
The bios does seem to freezeup sometimes when trying to access or restart from being in the BIOS.
Would you be able to provide a live link please.
Super job with these mods gents 
Does anyone know if the x79 boards have an m.2 size limitation?
I am using multiple 500 GB units with no issues, but I can’t get a 4 TB to be recognized by my SABR. Newer machines see the 4TB just fine.
Thanks in advance
Rafal
Was that with the same PCIe adapter that you use on your SaberTooth?
Because it cant be a valid test if you used the onboard M.2 slots on a recent mb.
EDIT: I see… i was just curious about that, anyway i can’t confirm such limitation of 4Tb… we need confirmation from other users with the same size or model, that have the same NVMe mod on this old gen boards.
Thank you for your report.
Sorry, i should have specified that detail…
Newer machines see the 4TB stick with same 4x adapter and also with an older 1x adapter.
While on the x79, neither adapter works with the 4TB stick.
Rafal
Hi all.
First of all, I would like to thank those who contributed to the bios update here. I downloaded the bios update file from here and applied it to my motherboard without any problems. I can get nvme speed at full value. I removed my old processor i7 3820 and installed E5 2697 v2. Everything seems to be fine. Only my video card (Rx7600) is running at x8 speed and I couldn’t do anything about it, but it’s not a big deal because there’s not much difference between x8 and x16 speeds.
I need your opinion on something. I want to upgrade my installed ram memory. I want to buy 8gb samsung ram or 16gb micron ram produced for the server. But I’m not sure if these memories will work in my system. Does anyone have experience in this regard? Can these server memory be used in E 2697 v2 and Sabertooth x79 combination? How will the performance be if used?
Hello everyone.
Thanks to those who contributed to the BIOS update. I downloaded the BIOS update archive (4801 bifurcation) from here and applied it to my motherboard without any issues. I can get full value NVME speed (pci-e 3.0*4).
My question is if anyone has used Lexar NM790 M.2 2280 PCIe Gen 4×4 NVMe 1TB SSD
When I plug it into the PCI-E 3.0 * 8 slot, the speed is PCI-E 2.0 * 4, not PCI-E 3.0 * 4. If it is installed on PCI-E 3.0 * 16, it is the correct PCI-E 3.0 * 4
PS : At present, the Transcend/Crucial/Kingston/Corsair M.2 in my hand is PCI-E 3.0 * 4 when plugged into PCI-E 3.0 * 8. Only Lexar will drop it to PCI-E 2.0 * 4 speed
MB: ASUS sabertooth x79
CPU: Intel® Core™ i7-4960X Extreme Edition Processor
VGA: GeForce GTX TITAN X * 2
Memory: A-Data DDR3 2133 2OZ 4GB * 8
Adapter: M.2 XPANDER-Z Gen4 2 sets of M.2 expansion cards
POWER: CORSAIR 1200W
M.2 SSD: Lexar NM790 M.2 2280 PCIe Gen 4×4 NVMe 1TB SSD * 2
please forgive my english
Hello
I own the ga-x79-up4 motherboard
It is convenient for me to test using your NVME mod BIOS (444*4)
I want to test whether ASUS HYPER M.2 X16 GEN 5 CARD can correctly use 4 M.2 SSDs on this motherboard