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Need load on 5v rail, what type resistor?

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amps = volts/ohms

watts = volts * amps

The resistor should be rated for at least three times the needed watts or it can run hot enough to melt plastic or even start fires that your father still won't forgive you for, day, after day, even years after you've completed your prison sentence for public endangerment (not that this has ever happened to me, really).
 
i don't understand the role of the resistance vaule. i don't know the curves. 2ohm vs 1k. essenially these resistors are small heat coils.

does anyone happen 2 know the formula.

1k will fry the PS, if so will 25ohm work?
 
Because amps = volts/ohms and watts = amps * volts:

A 1K resistor on the +5V rail will draw 0.005A and dissipate 0.025W.

A 25 ohm resistor will draw 0.2A and dissipate 1W (use at least 3-5W to keep it cool)

A 2 ohm resistor will draw 2.5A and dissipate 12.5W (use at least 40-50W to keep it cool).

If you can't find high-wattage resistors, you can combine lower wattage ones. For example, for the 2 ohm resistor above, you can substitute five separate 10 ohm resistors (in parallel, this will give 2 ohms), each rated for 5 watts (combined power 50W). Connect these in parallel, that is, each one goes between +5V and ground.

Some PSUs won't regulate their voltages very well unless enough current is drawn from some of them, like 2A on the +5V rail. Because of this, some PSUs have load resistors inside them (I think Antec TruePowers are like this).
 
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