In anything of this class of system -- doesn't matter if Dell or another brand -- it'll be whatever the manufacturer can source the cheapest.
I don't think I've ever seen QLC SSDs in Dell systems - yet, anyway.
If you already have the system, you can look up the specifications from the model number listed in setup (F2 at powerup). If you don't, you'll need to wait until you receive the system. What you receive installed in a specific system depends on what the assembly plant has on hand when your system is assembled; Dell uses models from multiple suppliers, so there's no guarantee you'll get a specific one, and no guarantee that two systems built even one after the other will have the same SSDs in them.
Thank you for your reply. I have note ordered yet. Before that, I try to assess the kind of ssd used by Dell.
I wonder if the Intel H10 Optane SSD proposed by others manufacturers is faster than the Dell SSD.
An optane module is not a true SSD. It acts as a cache for a much slower hard drive.
Any M.2 SSD, particularly NVMe, will be faster than any spinning hard drive cached by an optane module.
Also realize that asking about performance on a system at this level is a bit like asking whether a Honda Fit is faster than a Mazda 2. They're both economy models, with performance levels corresponding to that.
I agree, but I thought of the integrated Intel SSD with Optane.
which must be faster if the SSD is the same as Dell's one.
You can't directly compare an Optane module with a native SSD.
The SSD stores the data. The Optane module is just a temporary buffer space -- the data is stored on a spinning hard drive (an Optane module is designed for use with a spinning SATA hard drive, which then becomes the slowest link in the chain).
So, while an Optane module+ hard drive is faster than a hard drive by itself, the system is still far slower than a native SSD.
On the link I sent previously, you will see that Intel has developed a module integrating an SSD (not an HD) coupled with Optane. This module is used by brands like Asus for instance.
Anyway, I than you very much for your answers.
This still looks like a way to make a cheap, less reliable QLC SSD run more like a faster TLC or MLC SSD.
Unless you're in experimentation mode, I'd wait until the reliability verdict on these starts to come in. QLC drives will degrade faster than TLC (or the other SSD technologies). Only time will tell if these are long-term reliable, or simply disposable devices designed to last the length of the warranty before they fail.
The price pressure on entry level systems is enormous, and just a few cents' difference in cost can make the difference in a manufacturer using a cheaper drive. And as with everything sold at the price level of the 3000 series Inspiron/etc., literally everything come second to low cost for these systems.