Which ground wire should I use or does it really matter

**Major_Disaster** · 11-14-2006, 04:44 PM

I am in the process of ordering parts and laying out my wiring diagram. I need to ask, what on the surface appears to be a dumb question, but here goes; To power my system I will be using the 12+ as indicated in the image labeled J7, but does it matter which ground I use?

From my limited knowledge, I could use any ground that is available or even ground to the chassis if I desire. Is this a correct statement?

Thanks for everyone’s help. I have learned a lot “just lurking” and reading the various posts.

**MarkH** · 11-14-2006, 05:34 PM

any of the grounds on J7 will be fine

**MaXimaN** · 11-14-2006, 05:34 PM

I'm not sure I understand your question. Do you intend to power something other than the PC motherboard and hard drive from your ATX power supply? This is usually a bad idea, as the 12V line from an ATX power supply has a limited supply of current.

Or do you mean power your entire system just from the 12V line on the ATX connector pictured?

**Major_Disaster** · 11-14-2006, 06:48 PM

MaZimaN:

Thanks for your interest. Let me clarify a bit:

I am planning to use a DSATX (220 watts) to power my Dell SX270, an external HD (external USB enclosure with desktop 250GB HD) and external DVD ROM. I was planning to power the SX270 off the 12v rail, and the other items off the appropriate rails (to eliminate external 12 power supplies/converters).

I wanted to have a little head room for additional items should I decide to add additional items.

The image pictured is from the DSATX and shows which pin layout. I was curious about which ground wire to use or if it really mattered as to which ground wire was utilized.

Originally Posted by MaXimaN

I'm not sure I understand your question. Do you intend to power something other than the PC motherboard and hard drive from your ATX power supply? This is usually a bad idea, as the 12V line from an ATX power supply has a limited supply of current.

Or do you mean power your entire system just from the 12V line on the ATX connector pictured?

**Major_Disaster** · 11-14-2006, 06:49 PM

Thanks MarkH. Just curious if it mattered........

Originally Posted by MarkH

any of the grounds on J7 will be fine

**MaXimaN** · 11-14-2006, 08:14 PM

Originally Posted by Major_Disaster

MaZimaN:I am planning to use a DSATX (220 watts) to power my Dell SX270, an external HD (external USB enclosure with desktop 250GB HD) and external DVD ROM. I was planning to power the SX270 off the 12v rail, and the other items off the appropriate rails (to eliminate external 12 power supplies/converters).

Ahhh I see! In that case, it shouldn't be a problem. The SX270 stock PSU is 150W and the DSATX can cope with that on the 12V rail at a push. I'd be a little wary of powering anything more than the SX270 on the 12V rail though, especially if you intend to power the external HDD and DVDROM off the same rail. The SC270 uses an internal 2.5" drive - is it not possible to simply use that instead of your external unit?

**Major_Disaster** · 11-14-2006, 08:25 PM

The internal drive is small.........only 20GB...that is the reason for the external drive. I just happened to have a 250GB drive sitting in the closet. I was able to pick up an external enclosure for $12 (sorry...that was the last one). I have not purchased the DVD Rom yet.

I will ensure that everything is fused so hopefully it should not be a problem.

Originally Posted by MaXimaN

Ahhh I see! In that case, it shouldn't be a problem. The SX270 stock PSU is 150W and the DSATX can cope with that on the 12V rail at a push. I'd be a little wary of powering anything more than the SX270 on the 12V rail though, especially if you intend to power the external HDD and DVDROM off the same rail. The SC270 uses an internal 2.5" drive - is it not possible to simply use that instead of your external unit?

**gameboy** · 11-14-2006, 08:44 PM

splice your molex connector, yellow = +12vdc, black=ground, black=ground, red=+5vdc

**Major_Disaster** · 11-14-2006, 10:47 PM

gameboy,

Thanks for the info..........

Originally Posted by gameboy

splice your molex connector, yellow = +12vdc, black=ground, black=ground, red=+5vdc

**gameboy** · 11-15-2006, 12:05 PM

Originally Posted by Major_Disaster

gameboy,

Thanks for the info..........

np, its alot easier to use a molex connecter anyway, pick up a y-adapter for the 4-pin molex at any computer store, and splice it instead or using the one that comes with the DSATX....thats how i have my Soundblaster NX2(external) powered.....

keep an eye on the amp consumption tho.....don't want to draw too much off any one rail. i think on the dstax you have upto 15 amps PER rail.(which is alot better then some of the other DC-DC PSUs