Richdog
11-19-2005, 02:56 AM
Just out of interest do modular PSU's have any negative points when it comes to overclocking? I heard this reason for them not being as good as hard-wired:
Simply, Ohms Law : V=IR
Any soldered joint will have a lower electrical resistance than a similarly sized connecter, particularly if the connecters mating surfaces are not prefectly clean or slightly loose.
This isn't an issue if the joint/connecter does not need to carry much current, for example in signal level applications. However, when moving large amounts of current around, resistance in wires, joints and connecters becomes increasingly important.
Take a fictitious situation where you're powering a load from a 12V DC supply, and this load is quite power-hungry, drawing ~10Amps from the 12V source.
Say you used a connecter to connect the supply and the load - you'd need two connecters (one in the +12V line, the other in the ground line), each having a resistance of say .05 ohms.
This means you'd be dropping ~500mV across each joint, leaving the load with only ~ 11Volts.
If, on the other hand, you'd used nice soldered joints instead of the connecter, the resistance of the joints might be only .01 ohms apiece meaning the load is only losing 200mV, leaving it with 11.8Volts.
Reducing voltage drop and heating due to connecter and wire resistance is the main reason there are multiple red, black and yellow wires used to carry current from the supply to the mainboard (the load) in PC's.
Also, a manky or loose connecter carrying a lot of current is going to heat up and quite possibly cook itself in short measure.
This doesn't mean A power supply which adds a 2nd set of connecters in addition to the ATX one is useless. It just means you're adding another point where you're going to lose a small, but possibly important amount of voltage that chucks your highly overclocked system into instability.
Do hardcore AMD overclockers generally prefer hard-wired?
What are your opinions? :confused:
Simply, Ohms Law : V=IR
Any soldered joint will have a lower electrical resistance than a similarly sized connecter, particularly if the connecters mating surfaces are not prefectly clean or slightly loose.
This isn't an issue if the joint/connecter does not need to carry much current, for example in signal level applications. However, when moving large amounts of current around, resistance in wires, joints and connecters becomes increasingly important.
Take a fictitious situation where you're powering a load from a 12V DC supply, and this load is quite power-hungry, drawing ~10Amps from the 12V source.
Say you used a connecter to connect the supply and the load - you'd need two connecters (one in the +12V line, the other in the ground line), each having a resistance of say .05 ohms.
This means you'd be dropping ~500mV across each joint, leaving the load with only ~ 11Volts.
If, on the other hand, you'd used nice soldered joints instead of the connecter, the resistance of the joints might be only .01 ohms apiece meaning the load is only losing 200mV, leaving it with 11.8Volts.
Reducing voltage drop and heating due to connecter and wire resistance is the main reason there are multiple red, black and yellow wires used to carry current from the supply to the mainboard (the load) in PC's.
Also, a manky or loose connecter carrying a lot of current is going to heat up and quite possibly cook itself in short measure.
This doesn't mean A power supply which adds a 2nd set of connecters in addition to the ATX one is useless. It just means you're adding another point where you're going to lose a small, but possibly important amount of voltage that chucks your highly overclocked system into instability.
Do hardcore AMD overclockers generally prefer hard-wired?
What are your opinions? :confused: