I got a 1660 Super for my Acer Aspire desktop. It has an i5-8400 CPU. This is the one I got: https://amzn.to/2tGPAOO. Here's a link to the EVGA 500W power supply I used: https://amzn.to/2S7HSXq.
Amazon sells out of the other psu here's an alternate that has good reviews that's the same atx size: https://amzn.to/2ylgONi
If you don't want to upgrade the psu, I have run it with a 1660 super on from the original power supply in the Aspire(video to come). I think the beefiest gpu you can use going from a sata to 8 pin adapter would be the 1660 TI. I used a sata to 8 pin adapter cable to do it: https://amzn.to/2ZtSAvg or https://amzn.to/3bSbMFH
I used the second link ^ and it worked, I just didn't need a two pack.
If you want to put in a discrete graphics card for gaming/video editing, you'll probably need to upgrade your power supply. In this video I walk you through how to put in a GPU into your Acer Aspire desktop. I'm going to create another video with how much this helps in Premiere Pro, show benchmarks and how many fps I get in popular games such as GTA V, Tomb Raider and others. I haven’t seen such a big improvement with video editing and the reason why will be in the next video too.
Here's a link to the desktop if you're interested in checking it out: https://amzn.to/387wBvv.
The 10th gen i5 is $500 last I looked best deal so far: https://amzn.to/3hb0Gyb
There was recently a price drop on RTX 2060 to around $310: https://amzn.to/388rIma
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