6870 or 6850 for this PSU?

anon7mous

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Oct 5, 2011
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Hello,

I was planning on my buying 6850 (most likely Asus) but then 6870 prices dropped. Since I plan to overclock my CPU I have no idea can my PSU handle it. Should I go for 6870 XFX or 6850 and is it even worth it since some websites say that 6850 overclocked can outperform 6870. I even read that 6870 has problems with cooling :S

My system:

OS: Windows 7 64 bit
Chassis: Asus Vento A8
Motherboard: Asus P5E
Graphics Card: At the moment Sapphire HD 5670 512 MB
Processor: Core 2 Quad Q6600 2.4GHz (I plan to overclock it to 3.0-3.2 and buy Arctic Cooling Freezer 13)
Memory: 6 GB (667 MHz)
PSU: Asus model A-55GA (550W)

Drives: 2
Hard Drives: 1

Thank you in advance for your help.

 

nordlead

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The 6870 takes roughly 20W more than the 6850 (assuming reference models) so it hardly makes a difference.

By my rough calculation your system overclocked with a 6870 will need ~400W. Considering the PSU can put out 36A @ 12V (430W on two rails) you shouldn't have to worry about the 12V rail unless you also decide to overclock the GPU too.

I found an excerpt from a jonnyguru review (which doesn't appear to be available any more) and it said that the PSU puts out the claimed power. However I read another review on xbitlabs that claimed otherwise. I trust jonnyguru, but you have to choose for yourself who to believe when it comes to risking your equipment.
 

anon7mous

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Thank you for your replies.
I went on a site which calculates power consumption and I also get ~400W. Since it will be mostly used for gaming (BF3) I want to be more certain before I buy a new graphics card. Unfortunately I don't have enough money to buy both the graphics card and a new PSU :S





 

Djentleman

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You'll be fine... I'm sure you have a 12v rail with more than 20amps. And if its lasted you this long i'm sure it's probably not going to fail soon. Its when you start thinking about crossfire i think you should get worried.
 

anon7mous

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Thank you for your help. Unfortunately at the moment I'm quite low on money. I want to upgrade my PC so that I can do some decent gaming for a year or two and then I'm getting an entirely new PC.
After I buy a new graphics card I intend to overclock my CPU and get aftermarket cooler. Thats the best I can do :S
I wanted to buy 6850 Asus but since prices for 6870 xfx dropped I thought why not get a better card but this thing with PSU is driving me crazy :( I just hope it will be able to power everything after I overclock and get a new card...
 

beenthere

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It's very simple to accurately determine exactly what PSU power is required for your current or future system including the 12v amps. required by using the info. at the link below. There is no guessing involved or conflicting opinions. It's objective, electrical info. that everyone should learn to use. You will also be able to determine if you can upgrade to future Vid cards using the same PSU.

http://www.tomshardware.com/forum/314712-28-please-read-determine-power-required
 

nordlead

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as I said in my post Jonny Guru disagrees, but lost their review. Like I said, choose who you want to trust. Although the forum members at jonnyguru didn't agree with xbitlabs results.
 

Djentleman

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What do you mean?
Then Jonny Guru is wrong; 250 to 300 watts for a single 6870 is ALOT. I've seen people run the 6850 on a 430watt power supply. It all depends on what power supply you have. And by looking at his he wont have any problem powering it.
 

anon7mous

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I just want to inform you that I decided to buy 6870 in the end and I should have it in a few days. I also checked with Asus, AMD and XFX and they all said everything should be fine! Thank you all for your help and suggestions. :)
 

yummerzzz

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I'm living proof, and OP will be to, enjoy gaming OP!
I know I'm enjoying my HD 6870.