People don't realize how cheap hardware has become. Most vendors also have the ability to lease stuff for 0% (though that might have started to change), so you end up paying for a 3 or 5 year lease, which allows you to deduct vs. depreciate the asset on taxes. Sure you have to colocate it, but you could get a 48u colo rack for ~1k/month + ~1k/month for 1gbps link.

I used to buy dell outlet servers (which is their refurbed gear) all the time for folks who insist on dell, they end up being about 20-50% of the cost of cloud pricing if you are utilizing it with a full workload. Their stuff also includes a 3 year warranty with next day support, so it isn't very risky buying a refurbished server. There have been times where I found deals where the components could be parted out on ebay for more than the cost of the server. If you don't need support, there are tons of used servers on ebay / craigslist where you can get deals on 1-3 year old hardware that are good enough to purchase multiple spares.

For example, you can purchase a 2x 32 core server [1] for ~11k from the outlet store with next day support.

If you are running 24/7, with 64 cores over a 3 year period...

  Server Cost / Years / Days in Year / Hours in Day / Cores = Core per hour cost
  11000 / 3 / 365 / 24 / 64 = $0.0065/hour

If you wanted to go supermicro [2] with somewhat less reliable support, its a similar story. It would be a 1u dual 96 core (192 cores) box w/ 1.5tb memory for around ~30k.

  30000 / 3 / 365 / 24 / 192 = $0.0059/hour

You can recoup your hardware costs within the first year vs. running in AWS if your workloads are high enough to justify the hardware expense.

[1] - https://outlet.us.dell.com/ARBOnlineSales/Online/SecondaryIn...

[2] - https://www.itcreations.com/configurator/model/supermicro-as...