I posted the below, in the CPU/MB forum and after 125 views, have not receieved a reply. I think I should have posted in the Power supply forum, but I can't see a way to move postings, so had to copy and post again.

Would anyone please have any info on what type of PSU I should be looking for, I've been aching to order the system, just need info on PSU.

Thanks

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I am looking to build an always on Nas server, mainly to run PS3 Media Server and Squeezebox. It may be used an HTPC in the future, but for now its mostly for hosting video/audio files.

Because it will always be on, I am looking for a system with low energy consumption. I plan to buy the following components :


AMD 240e CPU
MSI 785GM-E51
4 Gigs RAM
Coolermaster 341 Elite
SAMSUNG 1TB F3 Eco HDD ( already have HDD)

In the future I'd like to add another 2 or 3 eco 3.5" HDDs.

The only thing I am missing is a PSU. I have no idea on how much electricty the system would consume on average/peak and therefore not sure how big a PSU I should get. Apart fromn the extra HDDs I dont anticpate adding anything else.

Any advice would be appreicated

Thanks

About 100W max. What is your lowest power option?

I would estimate about 30W AC at idle for everything except for the drives. Around 7W AC for each drive + 3 drives would but you around 50W AC idle. Definitely under 100W max. Any decent 300W PSU would be fine. You can get a 300W Seasonic 80+ bronze PSU for under $50 in the US. Or if you really wanted to get crazy you could probably do a PicoPSU with that setup. But that might be more work then it's worth.

For the configuration as described, 150W or better. If you really go to 4 HDD, 250W or better (people forget that HDD call for about 20W when the first spin up, even if their operating peak power is < 10W). If you are looking for an ATX form factor PSU, just get something of good quality in the 300-400W range.

Thanks alot for the info.

Seems like a 300W 80+ PSU is the way to go. Gives me a little extra headroom for additional HDD later on.

Cheers

Its not as easy as you may think to find a suitable PSU. I have gone through the stickys, postings, done searches online and found more specialised retailers such as watt-power, Kustom PCs and overclockers and still no joy

I am looking for a 300W 80+ MicroATX in the UK. The two options I have found are

http://www.scan.co.uk/Product.aspx?WebP ... ce=froogle

The problem with this is that it only comes with one SATA Power, is it possible to split it?


http://www.scan.co.uk/Products/330W-Sea ... -120mm-Fan

I like the look of this PSU, my only concern is that its 330W. I think my power requirements are quite frugal, for now only 1 HDD ( I forgot to mention also an Internal DVD writer).

I appreciate that HDDs require more power when spinning up, but if my system operates at about 100-150W, I would like to get no more than 300W, or is the difference between between 300/330 Negligible ? Also I have read that if the component draw is too low for the PSU, the system may not even power up, could this be an issue ?

You can buy 4-pin molex to SATA adapters.


The difference between 300 and 330W is not worth worrying about. The point of using a PSU with Wattage close to your requirements is to be in the efficiency sweet-spot. A 330W unit is unlikely to have a markedly different sweet-spot than a 300 or even 250W unit. For that matter, even going up to 450W or even higher wouldn't be an issue, it's just at a certain point you end up paying for more PSU than you need.


The configuration you posted wouldn't put you in danger of such a thing, especially so if you went to multiple HDD. Remember, the HDD use the most power right at power-on and that is the only time at which you would be concerned with too low draw on the PSU.