I was using Fusion360, primarily for its CAM functionality, specifically for CNC milling.

Initially I had it running on a 7th gen i7 laptop with GTX1050Ti graphics which ran just fine. I then upgraded to 12th gen i9 desktop, initially just using the built-in intel graphics. Fusion360 complained about inadequate graphics facilities, but it still ran. Later I added a graphics card.

I use it for 3d designs as it is free for a hobbyist. I like the product as I have done CAD before.

running on an old laptop, windows i7 with 8 GB of RAM and windows 10.

I use it occasionally for designing parts for 3D printing. It runs fine on my 2017 15" MacBook Pro (16GB RAM, an Intel Core i7-7820HQ, and AMD Radeon Pro 560 mobile graphics).

I use it for 3D printing - runs on my M1 MacBook totally fine along with my Ryzen workstation.

Depends on what kind of model you're running with. Complex - you may want something with a bit more ram.

Ge0rge: I have it on an HP Laptop running an i5 with 8GB of ram on W10. It complains occasionally when I get into projects with multiple parts, and the fans get a workout when you're orbiting.

Used to drive a router, plasma or printer.

Do you think this would do the job, if I add a dedicated graphics card?

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I don't think the integrated GPU will be good enough.  But. it looks like it has a few PCI slots - although it's hard to tell how many are free.

My plan would be for it to share the existing peripherals in my home office, so I only really need the box.

I'm planning on design in Fusion 360, 3D printing and (eventually) laser cutting and CNC.

Do you already use Fusion? TL;DR version - you might also want to have a look at OnShape, which is fully browser based so desktop specs largely irrelevant. Nice comparison of features here, plus there are some great tutorials from Michael at Teaching Tech. And should be a lower barrier to entry if you don't have to buy a new machine to run it.

Longer version: I have used Sketchup Make for woodworking and building plans for years. When I started 3d printing, I kept using Sketchup because it is what I was familiar with. It has some real limitations for designing parts and I've been meaning to adopt something better for ages. But it was almost always a case of "I'll just do this one thing in sketchup, then when I've got more time, I will get up to speed on Fusion". Rinse and repeat. But Sketchup has been progressively making the open source version harder to use and I have finally taken the plunge to upskill on something else (frankly, if they offered a Sketchup Make/Pro at a modest cost, I would have signed up for that but I can't justify thousands per year for something that is an occassional hobby). 

I had a good look at all the various options and settled on OnShape - still getting up to speed but have created a few basic 3d prints that seem to do everything as expected (albeit with a different way of getting there than sketchup). I'd suggest looking at the options - they all have pros and cons, and the free/hobby versions are subject to change at any time. Onshape to me seemed to be a really good design and modelling tool. It doesn't have the CAM features of Fusion, but in my limited dealings with Fusion, I have had way more trouble getting the CAM to work as expected and invariably end up using dedicated (and simpler) slicer or CAM software to generate the GCode.

YMMV, keen to hear what you settle on.

mdf:

 

Do you already use Fusion? TL;DR version - you might also want to have a look at OnShape, which is fully browser based so desktop specs largely irrelevant. Nice comparison of features here, plus there are some great tutorials from Michael at Teaching Tech. And should be a lower barrier to entry if you don't have to buy a new machine to run it.

 

At the moment I'm using Tinkercad 😊.  It's basically a CAD programme aimed at kids but it's an easy environment to get a handle on the basics.   I've made a few designs in it and 3D printed some on a friend's machine and been happy with the results.  Fusion seemed like the natural progression from TinkerCad.  I haven't seen OnShape so I'll check it out. Thanks.

mdf: I still use tinkercad for some things too! Easiest way to get a bolt thread and nut to match!

I've got half a dozen little switch enclosures on my boat, all vacuum-infused using moulds printed in tinker cad. 

I love vacuum infusion at small scale.  It's total overkill, in an inefficient fizz boat, where grams absolutely do not matter. But it saves expensive resin and it's fun to watch. 

Professionals would be horrified by my setup!

I use Fusion 360 to teach CAD to electrical engineering students. Now Eagle is included we use that part to create circuit boards etc. then use the 3D workspace to create, for example, the boxes that the design goes in.

You will have no issues running it on anything really as it offloads any hard stuff to the cloud.

It is improving, but AutoCAD is still far better for creating the sketches and I would be using Inventor or SolidWorks if I was getting into large assemblies.

It takes a bit of getting used to but since the basic version is free it is probably worth the pain.