Although once you reach 4 2080ti, you ought to consider switching to a titanium grade psu and rewiring if you're in a 100-120v country. If you're feeling cheap, just steal the phases from two different circuits. Last I looked, most psu operate around 5% lower efficiency on 115 vs 230.
I chukled, but more seriously, if you can't rewire your house to get a normal 240V circuit, you should not be fucking around with hacks like above.
How much is your electricity? I currently run 12 GPUs in my garage pretty much non-stop. 4 GPUs per machine, 3 machines. Each machine is about 1.2KW on average (I can tell because each machine is connected through its own rack UPS), or 13.2 cents per hour, or $95/mo. Which, IMO, is not bad at all. That's less than $300 per month for 12 GPUs.
Several issues: 1. electricity bill is still an issue, I've been paying anywhere between $500 to $1000 per month for this workstation (always have something to train). 2. something with a decent memory size (Titan RTX and RTX 8000) cost way too much; 3. once you reached a point of 4-2080Ti-is-not-fast-enough, power management and connectivity setup would be a nightmare.
Would love to know other people's opinions on the on-prem setup, especially whether a consumer-grade 10Ghe is enough for connectivity-wise.