Hey guys, hope you can help me, I'm a total noob when it comes to electronics. What I want to do is cut the molex cables that come from the power supply and then join them using XLR connectors, like this: Don't mind the crappy photoshop, it was just to show you what I need to do... My question is: Is it possible? If so, how? And with the sata power cables is it also possible? Thank you bit-tech for the great boards you provide us and excuse me for my bad english, i'm from Portugal (F.C.PORTOOO!! )
It's possible with the power cables, Do you have a good supply of XLR Connectors? You would need some 4 pin XLRs and a soldering iron. I don't know about SATA cables. Jimbo
3 pin SLR is sufficient for normal molex plugs (the one in that picture) for you can join the two ground wires (black ones) SATA should be working both with 3 and 4 pins... my psu (cheap one) has 4 leads, of which two are black... so that again leaves 3 pins. Some PSUs have 5 leads towards SATA power connectors, adding an orange wire. My harddisk (Maxtor Diamond Max 10) seems to work with both types
good boy anyways. this has already been done several times, so yes, it is possible look for it on this forum
All you do is 1. cut the wires 2. connect the male and female XLR plug ends 3. if the terminals are not numbered already use a multimeter to find out which solder pins/terminals are congruent and label them with temporary number labels 5. if desired make a box to house the PSU end female connectors and mount them in it 6. solder the PSU wire ends consistently using the same wire placements for each female XLR connector 7. solder the connector wire ends consistently using the same wire placements for each female XLR connector
correct me if i'm wrong, but the whole point of the two ground wires is to keep the potential of the +5v and +12v lines at those voltages. If it were AC, then using two hot leads would mean 220v with a common neutral line. With DC, (i think) you have to have a separate ground for each voltage. But the wierd part of that would be for SATA (+12v, +5v, +3.3v) and only 2 grounds. XLR connectors come in a variety of pin quantities (mouser.com or digikey.com in the US) so you could use 3, 4 or 5 pin styles, depending on what device you're connecting. As of SATA and SATA2, the +3.3v rail isn't used for 3.5" HDDs because they still only need the +5 and +12 rails. Smaller drives (<= 2.5") may eventually use the +3.3v, but for now even notebook SATA uses just the +5v rail. Cpt Slug: have you successfully used a 3 pin connector for standard IDE drives?
With DC you have to have all the 0V lines the same as floating earths become a problem with potential differences between the 0V lines, the resason there is more than 1 0V is for noise (ripple on the DC), I think. cpemme seems to be the subject matter expert on this. Jimbo
IIRC its for noise on the line, as well normally you should have a ground wire for every power wire, just so you have enough grounding for the maximum power output of the power leads, else if you were to max out the 5v and 12v lines with a single ground, the ground wire is the one that would end up melting and heating up, or causing general issues. A simple HD is no cause for concern most draw at max 1.5a on each line, and many well below that. The molex wire is plenty thick enough to carry that. Also combinng both grounds into one will cause you no issues. A good many drives combine the two wires anyway, and they are physically connected on your power supply as well. You probably do not want to connect more than 3 or so drives with grounds combined in this fasion, but for one or two your good Just make sure you solder good clean connections, and you should be home free. Also a note about the SATA... I am not sure any drive currently uses the additional 3.3v line... Notice that 99% of sata adaptors for molex make no attempt to get the 3.3v line elsewhere, and motherboards never include ones to get power from the 3.3v line. Another clear indicator that your drive will not need the 3.3v line is if it takes a regular molex plug as well. Now get to it and post some pictures when your done!
I don't use 3-pin XLRs. I prefer to use 4-pin or 5-pin Circular DINs. XLR microphone connectors are too pricy and bulky for my tastes.
Thank you for all the replies... I think i'm seeing how it can be done now My only problem would be the soldering iron as I don't own one and i've never soldered anything, but i'll give it a try and if i succed (I hope so) i'll post pictures later.. Thanks all for the help
Aha, a much better alternative. I was thinking of the ammo can mod with the XLR mouse/keyboard plugs on the front.
Unless you have multiple rails or something, all black leads will solder to the same pad inside your PSU. Likewise, all yellow, red, etc will go to the same place. There are two black for supporting more current. If you join them at once place, it isn't going to matter. The increased resistance from joining the two wires at one pin is negligible. If you were to remove one wire completely, such that there were only three wires, then it would, with devices that draw enough current, become a problem. But otherwise it's not an issue. Resistance is a factor of distance through the material as well. By the time it makes a differences, it's likely the rest of the wires will have already melted.