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from the amd site it looks liek they claim 550 watt is good enough for two 4850's in crossfire. if they suggest it... it must be a pretty safe estimate.

i have 4 hard drives, and e5200, 4gb ram and an old audigy 2.

i was considering upgrading to TWO 4850's, amd 955, 4gb ddr3, and having only three hard drives. 550 watt sounds measly... can it power all that?

how much power do hdd's take?

550 is enough, but it depends on the quality of that 550

What is the brand and model of the PSU?

If it's a good PSU it should power those with room to spare but it's hard to say without knowing exactly what PSU it is.

Yes - check my sig. I'm seeing at most 380W drawn at the wall, so only about 325W supplied by the PSU even assuming an optimistic 85% efficiency.

A good 500-550W PSU should be fine if the rest of the system isn't too extravagant.

http://www.newegg.com/Product/Product.a ... 6817182031

Rosewill 550 watt. its uh... its okay. ^_^
i havent busted out my amp meter and tested it, so i dont really know how well mine is performing.

i guess if i get my parts, ill just treat it like a rear axle. if it aint broke dont fix it.

Should be fine.

yeah its hard these days to know what a psu should be capable of handling. with all these absurd setups, you never know quite how much you need. i remember when my antec 430 true was a nice 100 dollar purchase. when that was all one would pretty much ever need. then again, i wasn't ever much of a huge beefcake rig builder. im still having trouble justifying anything more than my e5200 and single 4850. every game out there runs perfectly fine on it... /

in a way im happy becuas ei have a cheap comptuer that plays any game, but on the other im sad because i dont have a bad excuse to build a new computer

shaq_mobile wrote:

yeah its hard these days to know what a psu should be capable of handling. with all these absurd setups, you never know quite how much you need.

Go read any good review of a high end graphics card. Skip to the "power consumption" page. Unless it notes otherwise, those idle/load numbers are for the complete test system, a system that should include a high end processor and mobo. That's how much power you need.

FuturePastNow wrote:

shaq_mobile wrote:

yeah its hard these days to know what a psu should be capable of handling. with all these absurd setups, you never know quite how much you need.

Go read any good review of a high end graphics card. Skip to the "power consumption" page. Unless it notes otherwise, those idle/load numbers are for the complete test system, a system that should include a high end processor and mobo. That's how much power you need.

Like this.
http://techreport.com/articles.x/16681/11

shaq_mobile wrote:

in a way im happy becuas ei have a cheap comptuer that plays any game, but on the other im sad because i dont have a bad excuse to build a new computer

Get yourself hooked on Folding and you will be upgrading in no time.

tsoulier wrote:

FuturePastNow wrote:

shaq_mobile wrote:

yeah its hard these days to know what a psu should be capable of handling. with all these absurd setups, you never know quite how much you need.

Go read any good review of a high end graphics card. Skip to the "power consumption" page. Unless it notes otherwise, those idle/load numbers are for the complete test system, a system that should include a high end processor and mobo. That's how much power you need.

Like this.
http://techreport.com/articles.x/16681/11

Yep. Multiply those numbers by (being conservative for a really good PSU here) 0.8 and you'll have something close to the actual DC output. Then I've heard as a rule of thumb to not load a PSU over 75% of it's rated output, though that's probably unnecessary for a good-quality unit.

So, using that TechReport article as an example, a high-end PC with two 4850s in Crossfire draws 447W load, assuming 80% efficiency that's an actual output of 358W. Applying the "75% load" rule, a 480W power supply should be sufficient for that system. I'd make that a Seasonic or something similar, somehow I doubt a Rosewill would do it.

If I we're you I would go with a bigger power supply to leave some room for upgrading, such as another hard drive. My system specs include 2 hard drives and just 1 4850 video card, and I went with an OCZ 700 watt power supply. I don't think I went overkill, I just want to be able to expand later, or if I build a bigger system, I can use the power supply from my old system and save money.

dustyjamessutton wrote:

If I we're you I would go with a bigger power supply to leave some room for upgrading, such as another hard drive. My system specs include 2 hard drives and just 1 4850 video card, and I went with an OCZ 700 watt power supply. I don't think I went overkill, I just want to be able to expand later, or if I build a bigger system, I can use the power supply from my old system and save money.

Thats way overkill , unless you plan on adding 5 hdds and a top end cpu overclocked with two 285s.
Check out my sig below the Phenom is overclocked to 3.6 with a 4890 runs fine with a 500 w but , it is Seasonic.

FuturePastNow explains it pretty well.

I use TR's primary reviews as my reference for all things computer. I just thought those numbers in the power consumption were for the gpus themselves, not the full system load. That... changes alot of things removes liek 200-250 watts from my estimations. Thanks for the help guys!! Oh, and my rosewill is a 550 watt, i probably wouldnt stick with it if it was 500 watt, but im feeling pretty cheap, so i guess ill take my chances.

I don't want to upgrade my pc all the time, I want to spend money on my caaaar. i wanna stroke my 350 and get a big hydraulic roller with some 1.6 rockers and some legit heads. that adds up really quick. ill need to get the tranny rebuilt, thatll probly cost me 1000 easy for my 700r4. i also will need better rear tires, my elco needs all the help with traction it can get.