Use a modern, safe ATX power supply with vintage motherboards that need an AT power supply.
New
ATX PSUs don't have the negative-5V rail, and so ISA cards that need
this won't work, such as a small number of old sound cards. Most old sound cards don't need -5V however.
The green and black terminals connect to your standard front on/off power switch.
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eBay doesn't allow custom shipping service names.
"Economy" will be tracked airmail to most countries, but untracked to a few more remote ones. 1-2 weeks usually, but can take longer.
"Expedited" will be DHL Express. 3-4 days usually. Exact quotes vary depending on the country. I can refund if you are overcharged.