HD 7850 reviews

They make noise, too.

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CA_Steve
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Re: HD 7850 reviews

Post by CA_Steve » Tue May 28, 2013 6:14 am

Powercolor passive review @ Techpowerup added. I'd hold off purchasing this one until they update the BIOS.
Idle power consumption with a single monitor is high, very high. The reason is apparently a misconfigured BIOS that runs the card at full memory clock instead of the 150 MHz of the other cards.

Dmesg
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Re: HD 7850 reviews

Post by Dmesg » Sun Jun 02, 2013 4:52 pm

bluehat wrote:I don't have any laboratory measurements to show, but lot of people are saying they are getting same high gpu temps and fan speeds with Furmark stress test and with W2 ubersampling enabled. W2 isn't cpu limited or memory bandwith limited, just raw GPU processing with ubersampling, and power draw is similiar to maximum.

W2 is also partly a stealth genre game, so you really don't want any undersized or loud case or video card cooling when playing the game.
No one can play W2 with "ubersampling" enabled anyway.

CA_Steve
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Re: HD 7850 reviews

Post by CA_Steve » Wed Jun 26, 2013 6:56 am

Powercolor Passive review @ HardwareLuxx added.

CA_Steve
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Re: HD 7850 reviews

Post by CA_Steve » Fri Aug 16, 2013 7:20 am

Powercolor passive @ etekniks added. They attached 120mm and 140mm fans to show improved cooling...but only ran the fans at stock speed :roll:

eclipsevv
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Re: HD 7850 reviews

Post by eclipsevv » Mon Nov 18, 2013 12:50 pm

Just built a system with the Powercolor HD7850 SCS3.

No problem at all with temperatures in a case with decent airflow (Antec P183 with two fans @800rpm); they reach 75°C after two hours at full load.

The memory clock issue is still there, it's fixed by default at 1200MHz and idle power is high.

However it's really a non issue: you can set the memory clock at 600MHz in the AMD Overdrive panel and it will automatically switch back to 1200MHz in 3D. This way you can decrease idle power by at least 10W to almost normal levels.

Anyway, I don't think this was done by mistake. Probably they used low power RAM on this board, and the display flickers visibly when the memory clock changes. I'm sure they chose to set it at 1200MHz in 2D & 3D to avoid complaints about the flicker.

eclipsevv
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Re: HD 7850 reviews

Post by eclipsevv » Mon Nov 18, 2013 1:59 pm

Further details after more tests, this could be useful if you choose this card (even with the issue, I definitely recommend it!).

You cannot independently set 2D and 3D memory clocks on this card, but you can still use a workaround: AMD does not allow a memory clock more than 150MHz lower than the core clock. So, 750core/600mem is ok, 860/600 is not (and the memory clock automatically goes to stock 1200MHz).

You can create the following 3 presets in CCC:
  • Stock: 860/1200 -> in 2D becomes 300/1200, in 3D becomes 860/1200; no flicker but idle power is high!
  • Low Power: 750/600 -> in 2D becomes 300/600, in 3D becomes 750/600; there's a 20% penalty in 3D but idle power is 10W lower with no flicker (3DMark11 goes from 6426 to 5121 on my system).
  • Auto: 860/600 -> in 2D becomes 300/600, in 3D becomes 860/1200; no penalty but there's flicker on memory clock switch
Hope that's useful for whoever wants to buy this card.

kakua
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Re: HD 7850 reviews

Post by kakua » Fri Nov 29, 2013 2:50 pm

How does the PowerColor passive compare (roughly) to the active ones? Is there any significant difference between just that one and the active ones, if you know what I mean?
And another question, do we know if they fixed the single monitor idle consumption problem?

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