What size PSU is best for my computer?

[Daniel Boone]

Here is what I am putting together...

CASE: ROSEWILL CHALLENGER
Motherboard: ASUS M4A89GTD PRO/USB3
CPU: AMD PHENOM II X4 965 BLACK EDITION
GPU: HIS H545H1G Radeon HD 5450 (Cedar) 1GB
HHD: Western Digital Caviar Black WD6401AALS 640GB
MEMORY: 8GB PNY MD4096KD3=1600_X8 XLR8
OPTICAL DRIVE: LITE=ON IHAS424-98 LIGHTSCRIBE
OS: MICROSOFT WINDOWS 7 PROFESSIONAL 64 BIT

Monitor/ HDTV: 23" SAMSUNG P2370HD-1

Recently I used a configurator [http://extreme.outervision.com/PSUEngine] to see what size PSU I needed and with my specs it said the minimum should be 309W with a recommended of 359W.

I have also read that the "ideal" is for the operating watts be 50% of the PSU. In other words...if your system operates at 300W the PSU should be a 600W. That said, do I NEED a 700W or is it better to just get a 450-500W?

 

[JackNaylorPE]

Plug your components into here:

http://www.antec.outervision.com/

Don't forget to include things like capacitor aging which should be low for a hi end PSU and higher for a low end.

While it is true that PSU's are the most efficient at 50% load, that does in no way mean that you "NEED" to operate at the BEP (best efficiency point). Your 650 watt PSU, may be say 90% efficient at 325 and 88% efficient at 500. That being said, given current price structures, I would never buy a PSU less than 650 watts.

I'd look for an Antec EA-650 / Antec TP-650 or Corsair TX 650 .... 500 watt PSU's of comparable quality are usually only around $10 cheaper.....most are not of comparable quality even if they are the same brand....for example, while Antec EA/TP/TPQ/SG/HCP/HCG are all good to very high quality, the Neo/Basiq lines are cheap OEM level units

 

[etk]

A quality 450 to 500w will be more than enough, but...

What is the application of the computer? While a 5450 was a good choice for me (I needed 3 video outputs, and I don't play games) The 890 has pretty good IGP, since you only have a single monitor listed, you may be better off using your on board graphics or getting something more robust.

 

[iceclock]

OCZ ModXStream Pro OCZ600MXSP 600W for 60$ delivers plenty power or antec

basic 550watt for 64$

will do the trick

 

[Daniel Boone]

Best answer selected by Daniel Boone.

 

[Onus]

Running flat out, that PC likely won't pull more than 200W. Sitting mostly idle, 75W is more likely. With no plans for a more powerful video card, a 380W Antec Earthwatts would be my choice for this machine, and I'd expect it to run happily for years.