Question M.2 speed on fully populated Asus Formula board?

tclancey

Honorable
Jun 6, 2015
12
0
10,510
Hi there. I have an Asus Rog z690 Formula board which I'm currently running in before deciding it's ready for a permanent desk position.

While the manual is actually pretty helpful it doesn't list all the data I need to work out what's going on right now.

I'm fully utilising the 3x M.2 slots on the motherboard, the manual states 2 of them are G4 while one is G3, that's fine.
I have 2x Asus Strix 3090s in the x16 PCIe slots, so they should be running x8 each as I understand. (This is fine, they're mainly for Blender rendering)
I have 2x 4tb SSDs connected to the motherboard, a CD drive and a card reader.

What I can't find anywhere in the manual is how using both of the x16 PCIe slots will affect lanes to the M.2 drives. The machine is fully built now and is fully water blocked, so it's not at all easy to remove a thing and test and repeat, I'd have to fully drain and re-pipe etc.

The problem I'm facing is the current drive speed of 2 of the M.2s. The drive picked up as number 2 in the bios is the system drive which is reporting 7000 read write in WinSat, the other two are reporting around 500 each. While the 2x SSD drives I have installed are reporting their advertised 7000/5000 speeds.

So where is the drop in M2 speeds? Would I need to remove one of the GPUs to get these back to speed? If that's the case I'd sooner remove them and have 2 more SSds. With the motherboard comes the Hyper PCIe board for 2c M2 drives, I could populate that, but it would have to be plugged into the 4x4 PCIe slot, which I believe drops the first two PCIe slots to 4x4 also, I wouldn't really want this.

Can anyone shed any light on this board? This is the kind of issue that can make or break a build, it's usually extremely complicated and very difficult to find.

Thanks in advance folks.
 

Lutfij

Titan
Moderator
From the way the manual is structured, here in page 1-12, none of the M.2 slots that are on the board(not the add-on card) share lanes with the PCIe slots nor the SATA ports. As for your SSD's, might want to mention the make and models of said SSD's. Also, what BIOS version are you on for your motherboard?
 

tclancey

Honorable
Jun 6, 2015
12
0
10,510
No, I couldn't find anywhere that said they were shared. So why are the M2 slots 1 and 2 running so badly? I'm no bios expert but I can't see anything in there that would be problematic. I can't remember off the top of my head what the BIOS version is, but it's the latest release as of today.
The SSDs are FireCudas, but I don't see why that matters.
Anyone have anything I can try or check?