Adding u.2/u.3 drives to x570

So i have a pc with the following specs
Ryzen 3900xt
Asus pro ws x570 ace
128gb ecc
The onboard m.2 slots are already in use.

I have two new u.3 drives both are Intel/solidgym d7-p5600 1.6tb

I got an adapter for the u.3 drives that is not working very well. Im not allowed to use links but it is all electrical pcie to u.2 no controller or retimer.

Speeds are crap especially for two drives in btrfs raid 0. About 2000 read and 1000 write.

Im thinking i may go with an LSI 9300-8i and run two mini sas hd to u.2 cables and see how that does.

Does anyone know of a u.3 to pcie 4.0 solution? Or a better way to get these two drives on board and maximise speeds with the btrfs raid 0 setup?

I have a d7-p5600 6.4tb that I am using with a u.2 cable over pcie.

It is an nvme drive not a sas drive, so if you want to use an lsi sas controller, you need a 9400 minimum.

With a single drive on nfs I get around 7GB/sec

The drives are natively pcie4. All pcie u.3 drives will work on pcie connected u.2 cables.

No nvme only u.3 drives will work on a sas or sata controller.

Maybe you should try a different file system before you start purchasing hardware.

Also make sure that the drives that you are speed testing are not simultaneously being used for virtual memory.

Yep sorry pasted wrong model number

Supermicro AOC-SLG3-2E4T is my current pick. Oculink to u.2 should do it right?

That is a retimer, not a pcie switch. You don’t have a server motherboard, so you probably don’t have bifurcation. ie x4x4x4x4 mode. So a single slot will only support a single device without a pcie switch.

It does have bifurcation

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That should work great then. I have my drive connected to the pcie5 variant of an oculink cable without a retimer called mcio. You may be able to get away without a retimer since your motherboard is using pcie3 instead of pcie4 or 5.

Motherboard is pcie 4.

sorry, I read it as 370, my mistake.

I use the following items on the same mobo, which connect reliably on PCIe Gen4 speeds:

Please note that I use the shorter (0.5m) cable lengths.

Thanks for the input. I ordered a Supermicro AOC-SLG3-2E4T and will update thread with results

So i got the supermicro card refernced in last post and am having issues.

At first, the hba showed up with drives attached on bios. I installed fedora and ecerything was fine intip i rebooted and the u.3 drives attached to the hba had disappeared from boot options.

O tried rebooting several times and the drives reappeared once. Currently sitting at bios screen with no u.3 drives showing in boot options. Any ideas on how to fix?

Did you try it with a longer cable and then switch or did you always start with a 0.5m cable? I picked up the 0.75m version and now I’m wondering if I should have gone with the 0.5m instead.

I have relatively small cases and dislike cable management. I went straight with the shorter cables.

I should note that I just found out that apparently different NVMe drives are more or less sensitive to signal quality.

My Optane P5800X drives have no trouble with the above mentioned setup. I just received Micron 7450 Pros that have trouble sustaining speeds on all ports. They connect fine on PCIe 4 speeds, but when tested the data rates are inconsistent and drop on the port with the longest connection.

Okay, thanks. We’ll see how my luck goes with a slightly longer one. I wasn’t sure exactly how long I needed so I figured slightly longer was better.

Just to close the loop. I scrapped the retimer and connected the drive directly to minisasHD and it works perfectly. Im going with a motherboard upgrqde in another system to utilize the second drive.

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So far everything is working fine with the slightly longer cable and no redriver. I did have to change my mounting location however as there wouldn’t have been enough cooling. I don’t think the case designers considered the possibility of u.2 when they put 2.5 drive bays on the back of the motherboard tray. :smiley: