I dunno, I'm used to custom builds these days - whether I do it (2011 PC) or have a shop do it (CyberPower PC w/ my custom choices w/ the 3070). [shrug]
You'd have to find out what mobo's, PSU's, and whatnot are in there.
I think this part will be what most people stare at, as good GPU's ain't cheap in this market:
12gb VRAM RX 6700XT. Listen, that card is nothing to sneeze at, power-wise - it's going to be similar to 8gb VRAM RTX 3070 levels of power in Rasterization (Non-RT lighted) stuff. You also got more VRAM on the board too over the base 3070, so that'll help too.
I can't max out say WD: Legion at 1080p on my 3070 w/ RT b/c I don't have enough VRAM. I do wonder if the 6700XT could do it VRAM-wise, but....I dunno what the performance would be on RT On there.
If you're going to use RT - look, Radeon ain't the best at this thing normally. Make sure you sure if it got FSR support on a game especvially if you put RT on also, throw FSR on; you'll need performance boosts.
I'm not a big fan of Radeon, as I'm used to NVidia GPU's and their drivers & all - but still, numbers and power don't lie on the 6700 XT and its VRAM count.
And honestly - more older games doing NVidia DLSS support (like Control) really should ALSO add some FSR support, IMHO.
Here's some games w/ FSR support -
https://www.amd.com/en/technologies/radeon-software-fidelityfx-supported-games
Also, what AMD is able to achieve w/ FSR without any real say Tensor cores or AI stuff is really good, IMHO. It ain't far behind DLSS, IMHO - as I've thrown both on with my NVidia 3070 in Horizon: ZD Complete for PC; both methods look really good. Yeah, there's an edge for Nvidia and all probably b/c of the AI and Tensor cores - but, man, AMD ain't far behind there.
From the reviews - sounds like it can get hot. So, if you got room in there & the PC allows for it - maybe put some fans in there and/or a good AIO cooler in there?