[Problem] PCIe 3.0 Support for X79 Chipset MBs

BIOS/UEFI Modding BIOS Modding Requests
1

Hello everyone!
This my first topic but before maked research and no correct answer.

My bios is old AMI Aptio IV, config is X79 chipset with 1680 v2, GPU Nvidia, Nvme drive. The last two don’t work at Pcie 3.0, max is 2.0 if setted up “Target Link Speed: Force to 5.0 GT/s” if at “Auto” it works: 1.0, 1.1.

Found bios from chinese X79 mainboard with same version AMI, where Pcie 3.0 works.
The difference checked with AMIBCP at North Bridge > IOH Configuration > Port xx Link Speed at mine only option is 1.0 or 2.0, at the other is possibly to choose also 3.0. Tried to add that option. With MMTool 5.0.0.7 extracted uncompressed ffs file. Next with IFRextractor extract “into human readable text file“ to 5 files. Using MMTool and uncompressed file because extractors don’t finding IFR data when using other programs. In file 3 found where it is Port xx Link Speed and missing option. Write what should be, but any extractor don’t got reverse option.

Original one looks:

0x2A562: OneOf Prompt: “PORT 2D Link Speed”, Help: “Select Target Link Speed Gen1,Gen2 or Gen3”, QuestionFlags: 0x10, QuestionId: 0x28, VarStoreId: 0x1, VarOffset: 0xA4, Flags: 0x10, Size: 8, Min: 0x0, Max: 0x0, Step: 0x0 { 05 A6 65 03 6A 03 28 00 01 00 A4 00 10 10 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 }
0x2A588: OneOfOption Option: “GEN1” Value: 0 { 09 0E 6B 03 00 00 00 00 00 00 00 00 00 00 }
0x2A596: OneOfOption Option: “GEN2” Value: 1, Default, MfgDefault { 09 0E 6C 03 30 00 01 00 00 00 00 00 00 00 }
0x2A5A4: End { 29 02 }

Adding before End:

OneOfOption Option: “GEN3” Value: 2 { 09 0E 6D 03 00 00 02 00 00 00 00 00 00 00 }

Thinking to change values for every PORT xx Link Speed. Will it work?

Other possibility is to add only one option in “Target Link Speed” to get option: “Force to 8.0 GT/s” but string like this not exist.

Trying a lot of options, tools. Not every works. Checked that ffs file with HxD not find correlation. Don’t know how to make ffs file from that modded one. Possibly go wrong way. Thanks in advance.


Edit by Fernando: Thread title shortened

2

If you succeed in this one…you’ll be the 1rst one…
One thing is bios code/string variables…another is chipset/mboard design internal bus/lane connection from the OEM, Asus in this case.
Go for it…good luck.

3

It doesn’t sound good :melting_face: .

At this moment mission failed successfully. Changed PCIe 2.0 option to 3.0 but still it works max at 2.0. Possibly address to function 02 it’s disabled or maxed to 2.0.

I am not sure but in instruction or somewhere else was written that if you use two GPUs it works at max 2.0 x16. This is what I got one GPU and second slot NVMe.

obraz
obraz1267×684 80.6 KB

4

Its all about your mobo.. X79 ASUS mobos did support PCIe 3.0 + usb 3.0, but some from other vendors didnt.

AMIBCP into help, might unlock something.

5

At AMIBCP is no option to choose 3.0 only 1.0 or 2.0. Changed 2.0 option to 3.0 not only name but also adress from 1 to 2. But nothing changed. Still max 2.0.