Lackluster NVMe RAID-0 Performance increase?

[Durahl]

Greetings!

Yesterday I went ahead and installed a 2nd Samsung 970 PRO NVMe M.2 SSD into my ASUS Maximus XI Code witch each drive now populating one of the Motherboards M.2_1(SOCKET3) and M.2_2(SOCKET3) slots below the, unpopulated, PCIEX16_2 Slot ( only the PCIEX16_1 Slot is populated with a GTX 1080 Ti ).

The Upgrade was mostly happening due to the decreasing size of free space on the drives C:/ and D:/ partitions but I'd be lying if I wouldn't have liked a more substantial performance increase happening after adding the 2nd drive to the system.

Anyway... Here's two Screenshots of ATTO from before and after the upgrade:

Certainly, there has been an increase in write performance but it only matched the read performance from before which itself has remained unchanged.

Am I looking at a bottleneck caused by a wrong/missing UEFI setting or is this a hardware one?

[Datsun240z]

Interesting. i have dual 960 nvme pros in raid0 for about 3 years now. been happy until lately something happened and i cant get the computer to boot to windows to save my life.*

[Durahl]

Soo... Tec support got back in touch with me after reporting the issue and they're telling me - I quote:
"...the performance of the disks are so high that the pciE bus from chipset, is saturated, it is not possible to further increase the read / write speed"
So much for that...