Home server PSU advice

[alizee]

I'm trying to find the right PSU for my home server. I was thinking I might get this 550W 80+ platinum:
http://www.newegg.com/Product/Produc...82E16817121080

It's only 550W (but "over clocks" to 650 at lower efficiency), and according to the eXtreme Power Supply Calculator, I only need 500W at high load, which obviously would not be all the time. However, when I look at home server builds similar to mine, people are throwing in 800W+ PSUs. Any ideas?

Current server specs:
Core 2 Duo Q9450
4x2GB DDR2-800
Gigabyte EP45-DS3R
PCI GPU (only used occasionally)
2x PCIe x8 RAID cards, Highpoint RocketRaid 2720
2x 2.5" 250GB 5400RPM SATA hard drives
8 (out of 16) 2TB green 3.5" SATA drives.

Thanks in advance!

 

[fffblackmage]

I guess there aren't many PSUs that just come with all the SATA connectors you'll need, but that doesn't mean you have to spend $170....

For example - ENERMAX NAXN 82+ ENM750AWT
Ah, well, that comes out to $126, still quite expensive and 750W is even more overkill.

It'll be cheaper just to go with a good $50-ish 400-500W PSU and buy some adapters to get all the SATA power connectors you need.

 

[alizee]

I'm not that worried about the cost, I mainly want a good quality, efficient power supply. Is 550W enough for the system I have? I know you're saying 750W is overkill, but like I said, in a lot of posts that I've read with similar system specs, people are putting in 750W, or even 1000W PSUs.

 

[heymrdj]

Are your drives going into bays (like SAS backplanes?). Or individual? Most cards come with breakout cables that also include power by daisychaining molex. Most backplanes come with 2-6 molex ports on them to feed power to the drives that way. Are you using staggered spin-up on the drives or will they all come on at oncet? A quality 400W unit will easily handle that many drives on staggered spin-up (about 230W from the wall), but if you don't stagger, you'll need a quality 600-700W unit (pull from the wall is about 610W when all 20 drives boot at once on a core2quad setup). Staggered spin-up is your friend in the server world, reduces alot of stress on components and allows you to realistically downsize. It's doubtful your setup will draw any more than 250W from the wall when running (even with all disks accessed at once), so a 700W unit is going to be out of its efficiency range.

 

[Flat Mop]

Is this build meant to be a file server only? If so I think the Core 2 Duo is overkill. 550W is probably a bit excessive as well, I have run more powerful machines than this on a Corsair 430W. I would try and get something silent though, unless you are putting it in the basement or something.