Aurora R5, what is the PSU?

Base unit is 460W DM1RW

850W unit is modular.  460W unit does not have removable cables.

Optional unit is 850W

Model Numbers: D850EF-00, DPS-850AB-2A, 0N1WJD, 048Y6D

Rather than have to hunt for the specific cables you buy a regular power supply and add a micro sata power adapter for the optional optical drive.

https://www.amazon.com/CRJ-15-Pin-Slimline-Sleeved-Adapter/dp/B07FK5G2TF/

https://www.evga.com/Products/Product.aspx?pn=110-BQ-0850-V1

https://www.bestbuy.com/site/evga-850w-modular-bq-power-supply-black/5594501.p?skuId=5594501

One wierd cable.

The PSU part the computer came with is the 850W model. - We found it on the original order. So it should be in your e-mail. But if you need any other information, do let us know.

As a side question, is my motherboard compatible to upgrade to the i7 CPU? Sorry I'm new to pc building.

If it came with the Base I3 6100 you can update to I7 6700.

Dell however does not support "upgrading" the cpu.

https://www.amazon.com/Intel-Unlocked-Skylake-Processor-BX80662I76700K/dp/B012M8LXQW

Given the scalping price for these its probably better to buy a newer 8th or 9th gen machine instead.

or go for I5 6500

https://www.amazon.com/gp/offer-listing/B010T6CWI2/ref=dp_olp_0?ie=UTF8&condition=all

Ok thanks! I ended up ordering an i7 9700k because of a sweet deal Best Buy had.

Upgrading the power supply in an Aurora R5 is very time consuming and complex, because of the very cramped space and unconventional wiring.There are at least 5 things which are significant easier to replace.