OOPS! 6850 -> 5850 and Power Supply/AMP concerns

PSUs: The source of DC power for all components in the PC & often a big noise source.

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rpc180
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OOPS! 6850 -> 5850 and Power Supply/AMP concerns

Post by rpc180 » Mon Dec 06, 2010 8:09 am

To sum up, went and got a 3rd monitor for cheap which precipitated buying an eyefinity card. Originally targetted a 6850 but it turns out the chipset doesn't play well with my specific setup (image tearing in windows desktop on multiple make/models and driver versions). After excercising my credit I'm now using a XFX 5850 ZAFC which works well (and is very quiet).

Now to the problem: I figured a 6850 was fine for my power suppy (Seasonic X-400 with 33A on the single 12V rail). By most PSU calculators out there the X-400 is okay with the 5850 (http://www.raptoxx.com/calculator.php approximates max for the system in my sig at 23-25A of 33A which is about 75% and ~320W/400W or 80%). I do not overclock though the system is on 24/7 and folds. I am using a molex adaptor to cover the second 6-pin PCIe requirement connected by itself to a single perheperial port. Because of these numbers I feel like I'm borderline using this PSU in this setup.

The X-400 is within a 30-day return period; I was thinking of returning it and getting either the:
1) X-460 (5A more on the 12V rail)
2) S12II-520 (7A more on the 12V rail)
3) X-560 (13A more on the 12V rail)

Am I right in considering to swap out the PSU?
Last edited by rpc180 on Mon Dec 06, 2010 8:01 pm, edited 1 time in total.

ilovejedd
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Re: OOPS! 6850 -> 5850 and Power Supply/AMP concerns

Post by ilovejedd » Mon Dec 06, 2010 9:12 am

Seriously, the X-650 is cheaper compared to two of those models. Curious, have you measured actual power consumption?

rpc180
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Re: OOPS! 6850 -> 5850 and Power Supply/AMP concerns

Post by rpc180 » Mon Dec 06, 2010 9:41 am

ilovejedd wrote:Seriously, the X-650 is cheaper compared to two of those models. Curious, have you measured actual power consumption?
I don't have access to any power draw equipment so I tried to estimate using various online PSU sizing calculators. So far no random restarts or artifacting and I ran furmark for about half an hour so it *looks* stable. Am a little concerned about sustainability in the long term though.

Scoop
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Re: OOPS! 6850 -> 5850 and Power Supply/AMP concerns

Post by Scoop » Mon Dec 06, 2010 9:56 am

If you don't OC, you are more than fine. I'm running an OC'd E4500 and OC'd Radeon 6850 on my Seasonic 330W. My system most likely draws more power than yours.

rpc180
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Re: OOPS! 6850 -> 5850 and Power Supply/AMP concerns

Post by rpc180 » Thu Dec 09, 2010 10:06 am

Running great the past few days. Temperatures are higher in the case than before (more power out of the GPU, and now a fanless PSU). I am considering going back to the 120mm equipped seasonic 430 I was using before (RMA'd due to a fan issue) to increase negative air pressure in order to reduce case temps. However, it seems 33A on 12V line is sufficient to cover the system despite being rated at "only" 400 watts :)

Temps GPU: Gaming low 70s, Furmark 88C (!!) but stable.
Temps CPU: Idle 40C, Gaming mid-50s

Since I think furmark is boring and I don't play it, I'm just going to discount that temp...

Parappaman
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Re: OOPS! 6850 -> 5850 and Power Supply/AMP concerns

Post by Parappaman » Sat Dec 11, 2010 2:18 am

You will be fine following any of your options, but if you can take it back and get the cash you're saving, I'd get the X-560. They are essentially the same power supply (the X-400 is so overspecced you might end up pulling 600W from it without a hiccup, just like the X-560), but the added cables and fan will give you some peace of mind. :wink:

Scoop
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Re: OOPS! 6850 -> 5850 and Power Supply/AMP concerns

Post by Scoop » Sat Dec 11, 2010 9:10 am

88C is completely 100% safe for a GPU and your CPU temps seem quite low so don't know why you'd need any more fans..

rpc180
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Re: OOPS! 6850 -> 5850 and Power Supply/AMP concerns

Post by rpc180 » Fri Dec 17, 2010 5:44 pm

Yup, I'm going to leave it as it is as well. Still surprising that its capable of doing eyefinity gaming :)

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