Will this PSU run this AMD HD 4870?

jason_1234

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I currently have an Antec 400w-HCG and am looking to buy a 4870 from my friend.
I was just wondering if that psu would be able to run it.
I know it only has 1 6-pin pci-e cable, but he said there were "extra" cables. Is this just a lie?

If this PSU isn't good what would you recommend?

I was currently looking at something like this - OCZ ModXStream Pro 600W Power Supply

Or maybe this - OCZ ZS-Series 550 Watt 80PLUS Bronze Performance Power Supply

Oh yea and try to keep it under 50 dollars

Thanks
 
Solution
Cables lengths are better on the ZT series, so functionally you get the best of both. Again I think in terms of quality and performance it is fairly even with the ZS series.

Maybe you want to read some reviews for your self:
ZS Series 550W: http://www.jonnyguru.com/modules.php?name=NDReviews&op=Story&reid=248
ZS Series 650W: http://www.hardwaresecrets.com/article/OCZ-ZS-Series-650-W-Power-Supply-Review/1361

ZT Series 750W: http://www.jonnyguru.com/modules.php?name=NDReviews&op=Story&reid=262
ZT Series 650W: http://www.hardwaresecrets.com/article/OCZ-ZT-Series-650-W-Power-Supply-Review/1418

I don't live in the US and we don't have rebates here (UK) so I don't know how they work.

4745454b

Titan
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Is he currently using them both? Meaning its working right now?

Its really close. I don't know how much the 400W HCG can output on the 12v rail(s), but assuming it can do nearly all of it then it can supply up to around 33A. Assuming a normal system and no OCing you'll be able to do it. With the poor PSU running at/nearly 100% every time you play a game. You'd be better off getting a better PSU.
 
To get the second 6pin PCIe connector you would have to use two 4pin peripheral connectors and connect those to a peripheral to PCIe adapter (as explained here), leaving you with only two periperal connectors.

http://www.techpowerup.com/reviews/HIS/HD_4870_IceQ4/27.html
Shows a system with an i7-920 (which is probably more power hungry than a Q6600) and a factory OC'd 4870 drawing 293W peak from the wall under 3DMark03. So based on that yes a good 400W PSU should be able to handle it.

The HCG-400W has 30A on it's 12V rail.
 

jason_1234

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Yes he currently is using them both, i don't know what his specs are, but i know hes overclocked parts, so i assume i should be able to run it with my stock everything.
 

jason_1234

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Thanks, so it's an OK on the combo? and is $80 a good price for the two?
 

300W at the wall, which means 10-20% can be taken off that number to account for the efficiency of the PSU and power being wasted in the process of power being converted from AC to DC. So it is more like 90W. But again an i7-920 is more power hungry than a Q6600, so it is probably more than 100W of 'headroom'.
Stress/torture testing is something I would avoid as well, except to make sure that it does work.


Yes I think it is.
 

jason_1234

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jason_1234

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So it's not worth the extra 10 dollars for a 600W/550W? because they are on sale w/ rebate for 40, Would it just be extra useless power?
 

4745454b

Titan
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It might be worth it.

The system will only draw whats needed. If the system needs 300W, then 300W is all the PSU will send. The problem is if your PSU can only safely send 360W, then you are very close to the limits of what the PSU can do. This usually means extra heat as the PSU is working harder, and possible shorter life span. If your PSU can safely output 500W, then it has a better change of lasting longer, probably puts out less heat, and will be more efficient.

PSUs tend to be most efficient working between 40-80% of their rated output. (50-60% tends to be the highest.) A 400W PSU might be only 80% efficient supplying 300W of power, while a 500W PSU might be 85%. If so, then the 500W PSU will be pulling less power from the wall meaning it's saving you $$$.
 

jason_1234

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Yes I am sure. And in my experience review sites when they list system power consumption are doing so for the mains power draw.
In order to characterize a video card's power consumption, the whole system's mains power draw was measured.

The OCZ ZS series has quite long cables, so if you have a large case and care about routing cables behind the motherboard then go for that. While the cables on the ModXStream Pro are quite short, but has the advantage of being modular. I can't really separate them beyond that.
 

jason_1234

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and how about the zt series?
 
Cables lengths are better on the ZT series, so functionally you get the best of both. Again I think in terms of quality and performance it is fairly even with the ZS series.

Maybe you want to read some reviews for your self:
ZS Series 550W: http://www.jonnyguru.com/modules.php?name=NDReviews&op=Story&reid=248
ZS Series 650W: http://www.hardwaresecrets.com/article/OCZ-ZS-Series-650-W-Power-Supply-Review/1361

ZT Series 750W: http://www.jonnyguru.com/modules.php?name=NDReviews&op=Story&reid=262
ZT Series 650W: http://www.hardwaresecrets.com/article/OCZ-ZT-Series-650-W-Power-Supply-Review/1418

I don't live in the US and we don't have rebates here (UK) so I don't know how they work.
 
Solution

jason_1234

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Thanks to everyone for the help :)

But i've decided to go with his psu.
It turns out that the rebates are horrible, and i want to stay away from anything that is gonna cost me my precious time.

I wish i could give best answer to you all so i have to choose one when i am finished reviewing the comments.

Thanks again