Without any computer information especially the Make & Model of the PSU and CPU it will be sorta hard to suggest anything.
The major hardware that directly affects whether you can install one of the latest GPU cards is your PSU.
Generally you should have a PSU of around 750 or higher Metal rated PSU unless you purchase a budget cheap GPU card.
Seems like the Dell XPS 8300 has a 460 watt PSU installed which means you would need to purchase a low end GPU card: https://www.dell.com/bz/business/p/xps-8300/pd
Second if you have a weak CPU Processor that will bottleneck any of the latest GPU cards and not give you optimal performance.
This PSU website gives the Minimum PSU required to run a PC with various GPU Cards installed. Take a look at all the GPU card that requires a PSU of less than 450 Watts: http://www.realhardtechx.com/index_archivos/Page362.htm
Just quickly checking you can support two of the latest AMD GPU cards with your PSU:
Including the RX560, RX550 & RX540 GPU cards.
Either of the above GPU cards wil be superior to what you had before.
