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Thread ID: 92548	2008-08-14 09:09:00	GA-MA78GM-S2H power issue	stormdragon (6013)	Press F1

Post ID	Timestamp	Content	User
697245	2008-08-15 02:26:00	Why not tap the 5v for your LEDs off the 5v rail for the drives? That way they will only be on when the PC is actually running Can do, though it will just require me to completely rewire the circuit though to allow for the different connection and amperage, the great thing with USB was the low amerage meant the need for resistors was basically negiable.	stormdragon (6013)
697246	2008-08-15 02:40:00	I fail to see how you'd need extra components - both rails are still only 5 volts The LEDs will only carry as much current is being required by them, the PSU won't try to force 30 amps through them ;) Or perhaps you could manually wire in a switch that you can just flick off when you turn the PC off - or if you're clever - use a circuit that senses the absence of voltage from another rail and then switches the LEDs off when the PC is powered down	Agent_24 (57)
697247	2008-08-15 02:43:00	Trust me cheap little 5mm LED's don't like that higher amperage :) Put enough amperage to them and they tend to explode in my limited experience (gave up after 3).	stormdragon (6013)
697248	2008-08-16 23:29:00	Trust me cheap little 5mm LED's don't like that higher amperage :) Put enough amperage to them and they tend to explode in my limited experience (gave up after 3). Sure you didn't connect them to the 12v rail by mistake? or have a short-circuit somewhere? Because they shouldn't blow on 5v if you did your calculations right. 5v standby or 5v main rail is still 5v. The current capacity of the rail is the maximum it can supply, not what it will supply to the load on it. it will only supply what it's asked to (up to the maximum) Going by what you say, your hard drives etc should all be blown too, as they typically draw less than 1 amp on 5v and the PSU as we know can supply much more than that I have 2 PCs with LED Fans running of the main 12v rail. Neither of those have blown	Agent_24 (57)
697249	2008-08-17 04:01:00	Sure you didn't connect them to the 12v rail by mistake? or have a short-circuit somewhere? Because they shouldn't blow on 5v if you did your calculations right. 5v standby or 5v main rail is still 5v. The current capacity of the rail is the maximum it can supply, not what it will supply to the load on it. it will only supply what it's asked to (up to the maximum) Going by what you say, your hard drives etc should all be blown too, as they typically draw less than 1 amp on 5v and the PSU as we know can supply much more than that I have 2 PCs with LED Fans running of the main 12v rail. Neither of those have blown Relativelty sure were connected to the 5V rail, 12V shouldn't have blown them anyway. Yeah I know in theory the HDD's etc should also have problems as most don't draw much looking at a couple of IDE drives laying round next to me between .6A and .75A Got a whole lot of LED fans running of both 12V and 5V rails in various computers round here also none have problems. O well halve way though redesigning and building a bigger better curcuit anyway. Thanks for the help and suggestions	stormdragon (6013)
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