On Jan 30, 10:30 pm, Hugh Prescott wrote:
Sorry to disagree but I recently replaced two fuses on a early P-4
motherboard for a customer. Off brand motherboard.
...
I know there are some USB application chips that can current limit but
have not seen any on mboards yet.

I did not say defectively design boards do not exist. I said:
... the technology being that old.

In a market where computer assembler only buy on price, then
defectively design products will exist. Profits from selling
defective products to computer assemblers are just too good.

Meanwhile, the USB spec is clear. USB port current limit:
The preset value cannot exceed 5.0 A and must be sufficiently
above the maximum allowable port current such that transient
currents do not trip the over-current protector. ,,,
The over-current limiting mechanism must be resettable without
user mechanical intervention. Polymeric PTCs and solid-state
switches are examples of methods, which can be used for
over-current limiting.

You do not see such protection implemented? It only demonstrates
how many 'computer experts' need not first learn what is required -
too often only buy on price as taught in business schools.

That motherboard failure is directly traceable to a defective
design. How many other required functions are also missing?