Same card with different branding here.
Which slot did you put it in? What ssds do you use?
I had to move the card from slot #2 to #3 because of the RX 6800XT I installed, however previously, when in slot #2 in synthetic benchmarks my Adata SX8200 Pros were as close to ~3000 as the rest of the hardware permits.
In slot #3 I get around half that, which is fully expected.
View attachment 2225715
I was obviously disappointed I had to move the drives to a slower slot, tried using a ribbon breakout cable which proved fairly useless, however the speed difference actually makes zero impact on daily use and is perfectly unnoticeable.
Over the past 2 months I invoked every troubleshooting step I could think of. Removed all PCIe add-on cards, SATA drives in bays 2-4, external USB accessories and peripherals, optical audio, leaving only a graphics card and PCIe card with SSDs. Switched those two cards between slots 1 and 2 multiple times, NVRAM reset, updated the OC configuration, result was no change--read/write speeds on NVMes maxed at 1400MB/s. Next, I poured over my OC config.plist to see that there were no extraneous things installed or enabled; tried booting without installing NVMeFixUP; skipped FeaturesUnlock; etc. Last week I removed everything again, reseated the graphics card, put a blank SATA SSD in Bay 1, and via USB installer, I installed OC 9.1 to EFI of the SATA SSD/ Bay 1 and a clean install of Monterey 12.6.7 on the SATA drive. Next, installed 1 NVME on IOCrest PCIe card, as a storage-only, HFS+ volume, and inserted in slot 2. NVRAM reset. PCIe and NVME recognized, no change. Updated OC configuration to include card, no change. Re-installed 2nd NVME blade, with 12.6.7 as boot volume. Updated OC configuration, no change. Even tried reverting the blades to external drives, as they were under Mojave, but no change. Installed PCIUtilites to confirm PCI IDs of the blades and ASMedia chip, and PCI Tree.
So I'm fascinated that you got full read/write function on your SSD with no special action taken, before upgrading to the RX 6800 XT. And I find it odd that I can find no mention of these PCIe switch cards either working or failing to work with OC. (Here, Reddit, Discord, Facebook.)
I have RX 5600 XT. I opted for a dual slot card so I could maintain use of slot 2. SK Hynix Gold P31 1TB SSD NVME. Samsung 970 EVO 500GB SSD NVME. Under Mojave, I used the Hynix as a boot drive; erased and used as storage volume/scratch disk. Full 3000+MB/s read/write speeds in both cases. I did the same with the 970 EVO, for a while as scratch disk, then as boot volume. Under Monterey with OC, I've installed one blade only, set it as a scratch disk, also tried both installed as storage volumes, no OS. And currently using 970 EVO as my boot volume, with OC installed on EFI of SATA HDD in Bay 1. Read/write maxes at 1400MB/s in every case with Monterey + OC.
Actually, under Big Sur (which I otherwise really liked--stable and then some) the problem was the same. No real function of the PCIe switch. I had hoped the issue would get sorted in Monterey.
Edit (9 July 23)
I heard back from a developer who said OC has no plans to address this issue, so apparently no one using Open Core has PCIe switch enabled on these smart cards.
Last edited: