Question dxdiag showing wrong VRAM but GPU-Z shows correct VRAM?

[ApolloJ]

So I have a ZOTAC GTX 1650 GDDR6 OC Edition gpu. It should have 4096 MB of dedicated vram. However, when I checked the VRAM on dxdiag, it says I have only 3949 dedicated memory (this number is shown in the Display Memory section of the Display section of dxdiag, not in total memory). But when I checked the card through GPU-Z, it shows the correct amount of 4096 MB of GDDR6 memory. I also checked on Task Manager, Advanced Display Settings, System Information on Steam and even checked the graphics section of AC Origins and all of them shows the correct amount of VRAM (4096 MB). All except for dxdiag. Why is it like that?

 

[Cyberat_88]

OC Edition... may fail DxDiag.

 

[Cyberat_88]

Just for the heck of it I glanced first time at my Win 10 Dx-12 and it says 3728 MB. Windows normal.