It appears to be an OEM Intel 7600p drive in my new 7590. I'm getting sequential 1900 read / 1100 write which is pretty sad for an NVME SSD in a premium machine and quite a bit bazelow the rated speed of the 7600p (3000 / 1500) . I've tried it in both AHCI and NVME, all drivers are current, PCI-e power management is disabled, and it's running on all 4 lanes at full speed according to HWInfo. There is minimal info on the drive and no firmware upgrade available through Dell. As best I can tell, this is as good as it gets. If so, I'm annoyed and may return just because of this. 

Dell consistently sent out 7590s for review with Toshiba XG6 drives which are rated 3160 write / 3000 read. Not quite an EVO Plus but pretty close. I have an XG5 in my 9370 and it's been fantastic.

My system configuration showed the drive as a 3N94F which is described as "Solid State Drive,1TB,P34,80S3,Technical Sheet,XG6". I think you can appreciate why I assumed there would be a Toshiba XG6 or something in the same league in my machine. I spoke with one 7590 who got a Hynix 1 TB in his unit and we ran Diskmark for comparison. 35% better than the Intel but still below the Toshiba results.

This is bait and switch. I understand that there is no guarantee of a specific drive in a unit but it is reasonable to expect performance comparable to what is being sent for review and other 7590s.