Need advice about PSU

[Missing Ghost]

Hi everyone,
I have 2 questions about PSU for a server:
1) For this server I would be fine with 800w. However, most PSUs at this wattage are really priced. Since the motherboard has 2x ATX 20 pins connectors, can I use a second PSU? Could this cause any problems/difficulties? Like if the two grounds from both PSUs come in contact, does it "shorts"/explodes lol. And what's about 12v 5v and 3.3 volts also does it do anything if two wires with the same voltage from different PSUs are shared by a device? Also any ground loops issues? I thought that would be really nice if it works, cause I will have 2x more plugs/wires. I know there is the CM Stacker that I can buy that fits 2x PSUs.

2)For a RAID array with multiple drives.......
I thought that the voltage that I need the most is 12v since I thinks it's like:
12v:mechanicals components/motors etc.
5v:controller boards components
But, recently I saw somebody saying that what I needed the most was 5v. It has confused me a lot, especially since I saw that PCP&C sell 5v load resistors for RAID arrays. So, what's the truth?

 

[thescreensavers]

antec Smartpower 2.0 Mine workes very well.

 

[Fullmetal Chocobo]

Yes, you can use a second PSU. No problems with grounds between the PSUs. And there should be no reason as to why you would have a device powered by both power supplies, actually.

I have two PSUs: Seasonic 500w & 600w. 600w power mobo, video card, and primary (boot) hd. Secondary PSU powers fans (13 total), 6 hard drives, and a CD-RW. You just have to solder in a switch to turn on the secondary PSU. If you wish, PM me, and I'll walk you through the process...

Obligatory pic.

 

[Missing Ghost]

No it's ok I already know how to power them up, but I don't even need it for this one since it comes with 2x ATX plugs on the mobo.

 

[Fullmetal Chocobo]

Awesome. In that case, a hd uses about the same on the +12V and +5V lines, as far as amps goes (wattage is more on the +12V, because watts = amps * volts). The resistor might come into play, because PSUs have a max and a minimum for the lines. So they might put a resistor in there to be sure that it meets minimum capactites for the rail.

 

[Missing Ghost]

http://www.pcpowercooling.com/products/viewproduct.php?show=VLR

was talking about this^^^^

 

[Fullmetal Chocobo]

From my Enermax 460w PSU, there are minimums on the PSU:
+3.3v: 0.3A
+5V: 0.3A
+12V: 1.5A

So I'm guess that load resistor creates a load on the +5V so that you do not run the risk of not meeting +5V requirements.

 

[Missing Ghost]

bump