How much power do I need...

[Will de Beast]

just wondering how much power I would need for two 5850's?
(http://www.newegg.com/Product/Product.aspx?Item=N82E16814102889)

I'm planning on buying one, then adding another later, so I wanted to know how powerful of a PSU I'd need. The Sapphire website says 900W, but that seems high.

My Hypothetical Build

Motherboard: MSI 790FX-GD70
http://www.newegg.com/Product/Product.aspx?Item=N82E16813130223

Processor: AMD Phenom II 555 Black Edition (I'm planning on unlocking and OCing this later)
http://www.newegg.com/Product/Product.aspx?Item=N82E16819103846

Memory: A-Data Gaming series 4GB (x2 2GB) (I'm thinking of maybe adding another two sticks later)
http://www.newegg.com/Product/Product.aspx?Item=N82E16820211409

Hard Drive (Not sure if you needed to see this): WD Caviar Blue 500 GB
http://www.newegg.com/Product/Product.aspx?Item=N82E16822136073

 

[Will de Beast]

I know I'm taking a chance, but it's better than nothing, and I've heard the rate of success is pretty good.

How's this one

Corsair 850W Single Rail
http://www.newegg.com/Product/Product.aspx?Item=N82E16817139009

or

Corsair 650W Single Rail

They both have what I need, but I can't decide which one. The 650W is modular, blue, which complements my color scheme, and it's $10 cheaper. But I feel like it's a little weak.

 

[saint19]

Hi newcomer and welcome to the Tom's hardware forum.

+1 for the 650W, u don't need a 850W PSU unless that u want a 5970 Crossfire what like I see u don't want.

And for the HD this Samsung Spinpoint F3 is much better and with fewer price.

 

[Will de Beast]

Just to clarify, I want to have the possibility of upgrading to 2 5850's, which won't leave me with much for other things to power with a 650W I feel like.

Also, on the subject on that HD, I don't see a difference except for ratings

 

[saint19]

Here are the system requirements for the 5850

ATI Radeon™ HD 5850 System Requirements

PCI Express® based PC is required with one X16 lane graphics slot available on the motherboard
500 Watt or greater power supply with two 75W 6-pin PCI Express® power connectors recommended (600 Watt and four 6-pin connectors for ATI CrossFireX™ technology in dual mode)
Certified power supplies are recommended. Refer to http://support.amd.com/us/certified/power-supplies/Pages/listing.aspx for a list of Certified products
Minimum 1GB of system memory
Installation software requires CD-ROM drive
DVD playback requires DVD drive
Blu-ray™ playback requires Blu-ray drive
For an ATI CrossFireX™ system, a second ATI Radeon™ HD 5850 graphics card, an ATI CrossFireX Ready motherboard and one ATI CrossFireX Bridge Interconnect cable per graphics card (included) are required

The recommended PSU is for the entire system. Now with a 650W PSU u not only can handle a 5850 Crossfire u also can handle a 5870 Crossfire without problems.

WD Caviar Blue: Host to/from drive (sustained) 126MB/s
Samsung F3: Host to/from drive 250 MB/sec

You won't see the difference?

 

[saint19]

And u also can see here the AMD's recommended PSU for Crossfire. Can u see the Corsair 650W TX? because i can. Now if the 650W TX is recommended by AMD that is only a 80 Plus certified Why do u think that the 650W HX that is 80 Plus Bronze certified can't handle the rig?

 

[aznshinobi]

Don't get the corsair. I know everyone likes Corsair, sorry to burst your bubble about Corsair PSUs, but XFX is a better deal now The XFX Black Edition 750watt currently is priced at 119.99$ at newegg, the 650HX is priced at the same price. If he takes advantage of this deal, he'll save a lot for a great PSU. Plus, the 650HX is only bronze 80+ cert. as saint19 said. but the black edition is 80+ Silver Cert. plus not to mention the fact that there both still modular so yeaaa

For your ram, i'd recommend not using that but using this stick http://www.newegg.com/Product/Product.aspx?Item=N82E16820231277 plus you'll save 10$ with the code going on now.

 

[aznshinobi]

Also, side note on unlocking, it's not guaranteed so if it fails its your problem. I bought a 550 just to unlock it and sadly my chip couldn't unlock. But don't let that stop you from getting it, i just wanted you to know before you bought it thinking it was a 100% chance.

 

[Will de Beast]

Ok, just making sure, I'm on a tight budget, and I can't really afford to get the wrong thing, thanks for being patient with me.

I have switched to the XFX 750W, thanks for the suggestion.

I know it's not a 100% percent chance, but I can't really afford a Phenom II X4, so this way I at least have a chance

 

[Will de Beast]

WD Caviar Blue: Host to/from drive (sustained) 126MB/s
Samsung F3: Host to/from drive 250 MB/sec

You won't see the difference?

Sorry, didn't notice that statistic, thanks for the tip

 

[saint19]

^Don't worry we are here to help u.

 

[saint19]

:lol: Ok I'm here for help u.

 

[aznshinobi]

Also, if you can afford it Will, the Samsung F3 1tb is faster than the 500gb versions, and the 1tb WD Black. Because of the fact that over the 500gb versions, although just a minor increase in speed, the 1tb vers. has a 32mb cache while the 500gb vers. have 16mb cache. Over all the WD Black drives, the Samsung F3 1tb runs a 500gb platter, and the WD Black 1tb uses 334gb platter Soo in turn its faster.

 

[Will de Beast]

Alright, thanks for the help, that resolved the issue. azn, I'll consider the 1TB drive, but it would be a little out of budget, but $20 for 500 more GB is a good deal

 

[Will de Beast]

Best answer selected by Will de Beast.

 

[descendency]

http://www.newegg.com/Product/Product.aspx?Item=N82E16817151088

A modular power supply for $30 more.

Also, this is good (quick) reading:
http://en.wikipedia.org/wiki/80_PLUS