Question about Inspiron GPU upgrade

Check out the specs to make sure you have a power supply that supports any gpu you select. A low profile card that doesn't require 2 slots is best for an Inspiron. The 1660 super is not compatible. Check the measurements of any card. https://www.nvidia.com/en-us/geforce/graphics-cards/gtx-1660-super/

Default power supply does not support 1660.

Only Short cards like Zotac Mini Series will fit.

8 inches is max length of card.  12 inch 3 fan cards will not physically fit in the case.

https://www.amazon.com/ZOTAC-GeForce-192-bit-Graphics-IceStorm/dp/B07NMWYLRZ

https://www.youtube.com/watch?v=J81h1dHNwDk

Non Dell video cards will require Secure boot OFF.

If you dont want PSU outside you can use a GT1030 video card.

Non Dell Cards will require Secure Boot OFF in BIOS.

https://www.dell.com/en-us/work/shop/msi-gt-1030-2g-lp-oc-graphic-card-2-gb-gddr5-pcie-30-x16-low-profile-hdmi-displayport/apd/aa362018/graphic-video-cards

Power supply will have to be OUTSIDE the case because a real power supply will not fit INSIDE the case.

Bare Minimum recommended for a 1660 would be EVGA 700BR based on 150W combined power on 3.3v/5v rails and EPS 12v Spec.

You will also need Moddiy Adapter.

https://www.moddiy.com/products/Dell-Inspiron-3650-PSU-Main-Power-24-Pin-to-8-Pin-Adapter-Cable-30cm.html

https://www.evga.com/products/product.aspx?pn=100-BR-0700-K1

150W Combined is Not optional Spec

https://www.bestbuy.com/site/evga-700w-atx12v-eps12v-80-plus-bronze-power-supply-dc-dc-technology-black/6346160.p?skuId=6346160

EPS 12v SPEC for 3.3v and 5v and Combined