How to overclock a 7850 past 1050MHz?

Piklar · 27 May 2012 at 03:26

555BUK said:
This is the max stable I can get out of my crossfired 7850's. The useless MSI PE card is holding my lovely Powercolor back big time.

1125 / 5500 @ 1.21v (the Powercolor can do this at it's default 1.050v).

3DMark11 P11588 / Graphics 12927

THats a pretty decent score despite your OC limitations. Your score are almost identical to mine @those clocks. Am more fortunate with my case Corsair R400 which has 9 fans and very good airflow alowing stable crossfire clocks of 1200/1500 @1.25. Im not comfortable with that voltage and have had these for weeks now @1150/1375 @1.176, many hours of gaming now without a single issue.

555BUK · 27 May 2012 at 11:41

I have a few more observations regarding Crossfired 7850's.

Good
*Easy install, no problems with Catalyst drivers or GPU Tool and Trixx recognition.
*Works great with BF3, almost double the fps and really smooth too.
*Great for benchmarks
*Most games see 60-90% fps increase.

Bad
*Much Noisier within an MATX case.
*Temps much higher on MATX mobo
*The odd game quirks. SKYRIM sees very little fps gains and there is weird flickering at main menu screen (game itself runs fine). F1 2011 freezes at exactly the same instant whenever I start an R&D lap. I can race a full 30 laps without issue and fps is great but I cannot start any R&D sessions. Must be a game/driver bug.
*Overclocks are only as good as your poorest card.

My opinion is that ctossfired 7850's are great, but better suit Full ATX cases and Full sized mobo's where both cards can receive adequate cooling. I may end up DSR'ing my MSI PE card because it is a munter.

HeX · 27 May 2012 at 11:53

Seems the MSI PE cards wern't worth waiting for. Which is really odd as the TF3 cards are really good :|

wazza300 · 27 May 2012 at 11:55

could be msi's way of shifting some low asic chips? wrap them up in some fancy coolers n pcb?

petridish · 27 May 2012 at 12:53

I haven't had a chance to overclock my MSI PE yet but it does the 950 MHz on the core at its stock volts of 1.075V and has an asic of around 84% (if i remember all that correctly, I'm out at the moment). Seems like I might have got lucky?

Like I said I haven't had a chance to really test it yet and my internet is down at home so I haven't run any benchmarks. Anything I can do offline to give some feedback? I'd like to help out with the information on these cards

liamcrane · 27 May 2012 at 13:16

What does the asic actually represent?

555BUK · 27 May 2012 at 15:02

liamcrane said:
What does the asic actually represent?

ASIC represents the quality of the silicon wafer from which the GPU was was cut. Higher numbers equal better silicon and usually equate to superior overclocks at lower voltages and lower temps.

My turd of a MSI PE has just 72% ASIC and a default voltage of 1.21v. My Powercolor card has an ASIC of 84.9% and defaults at 1.050v. The VTX card I used when I started this thread was 86.2% and also defaulted at 1.050v.

Good ASIC's do not guarantee high overclocks, but it makes it more likely. What this proves is that no manufacturer currently cherry picks GPU's for their 7850's. Even MSI's premium overclocking card is plain luck of the draw. Just buy the cheapest 7850 you can find and keep your fingers crossed.

I personally will never buy an MSI card again. I could have forgiven a poor GPU on a cheap or reference card, but on one which screams overclocking greatness all over the box, I will not forgive or forget it. It's going back.

Generally
below 70 very poor
71 to 75 poor
76 to 80 good
81 to 85 very good
86+ lucky you

For me, the MSI card is useless because the minimun 3D volts allowed by BIOS are 1.21v. For a crossfired card with poor airflow this creates tons of heat and noise.

liamcrane · 27 May 2012 at 16:30

Cool thanks for that mate kinda makes sense really. I remember when i tested my MSI 7850 it came out at 87% i think so im guessing thats kinda good

HeX · 27 May 2012 at 16:30

Yeah its odd that the PE card had such high stock volts and is such poor silicon.

My TF3 is 83% and 1.083V stock. And the PE is meant to be better :S

Makes no sense! Seems you just got a really bad card

Twirlywoos · 27 May 2012 at 21:36

555BUK said:
ASIC represents the quality of the silicon wafer from which the GPU was was cut. Higher numbers equal better silicon and usually equate to superior overclocks at lower voltages and lower temps.

My turd of a MSI PE has just 72% ASIC and a default voltage of 1.21v. My Powercolor card has an ASIC of 84.9% and defaults at 1.050v. The VTX card I used when I started this thread was 86.2% and also defaulted at 1.050v.

Good ASIC's do not guarantee high overclocks, but it makes it more likely. What this proves is that no manufacturer currently cherry picks GPU's for their 7850's. Even MSI's premium overclocking card is plain luck of the draw. Just buy the cheapest 7850 you can find and keep your fingers crossed.

I personally will never buy an MSI card again. I could have forgiven a poor GPU on a cheap or reference card, but on one which screams overclocking greatness all over the box, I will not forgive or forget it. It's going back.

Generally
below 70 very poor
71 to 75 poor
76 to 80 good
81 to 85 very good
86+ lucky you

For me, the MSI card is useless because the minimun 3D volts allowed by BIOS are 1.21v. For a crossfired card with poor airflow this creates tons of heat and noise.

It's odd that because the TF3 I had also had default volts at 1.21. At the time I didn't note the ASIC, but with the 7850 I would always suggest the Sapphire non OC, and to look out for the OCUK deals which regaulary has it for £180.

555BUK · 27 May 2012 at 22:09

Thought you may be interested in some crossfire benchmarks for BF3.

Firstly, here are mu single card results taken from page 1.

Here's the Crossfire tests

Scaling is greater than 90% for crossfire. AMD have done a great job tweaking their drivers for this game.

Twirlywoos · 27 May 2012 at 22:30

does anyone get texture and shadow flickering when their card runs in Heaven?

If you look at 10-12 seconds into the video you can see the type of flickering I'm referring to on the cobbled stone.

http://www.youtube.com/watch?v=LNT9akRx0f0

Bartouille · 28 May 2012 at 01:01

majnu said:
does anyone get texture and shadow flickering when their card runs in Heaven?

If you look at 10-12 seconds into the video you can see the type of flickering I'm referring to on the cobbled stone.

http://www.youtube.com/watch?v=LNT9akRx0f0

Yea, I got that too. No worry, it's not your card.

Psymonkee · 28 May 2012 at 01:11

Well my VTX is installed and running at stock and fairly unobtrusive noise wise. A little louder than my old 9800GT w/ after market cooler but a big step ip!

What do I need to do crossfire etc?

555BUK · 28 May 2012 at 07:35

Psymonkee said:
What do I need to do crossfire etc?

For crossfire you need a second 7850. They work as a pair.

Psymonkee · 28 May 2012 at 09:36

I know that

Had a quick look around and it seems I need a new mobo first though

555BUK · 28 May 2012 at 10:26

Psymonkee said:
I know that

Had a quick look around and it seems I need a new mobo first though

Most mobo's with 2x full sized PCI-E slots can run crossfire. You just need to ensure that both slots can run in tandem at 8x or above.

glenimp617 · 28 May 2012 at 10:52

ASIC quality doesn't mean anything

MSI PE was around 84% but would not OC past 1060 :eek:

and to be honest, I'm not sure that was fully stable

They are the WORST 7850 cards on the market. Just ordered a PowerColor PCS+ so hopefully I'll have some decent clocks.

555BUK · 28 May 2012 at 11:25

glen8 said:
ASIC quality doesn't mean anything

MSI PE was around 84% but would not OC past 1060 and to be honest, I'm not sure that was fully stable

They are the WORST 7850 cards on the market. Just ordered a PowerColor PCS+ so hopefully I'll have some decent clocks.

I disagree with your first point.

ASIC quality matters. The lower the ASIC, the higher it's default volts. Typically, ASIC's below 73% have a default voltage of 1.21v, ASIC's above 83% have 1.075v and sometimes 1.050v. ASIC's in the middle use voltages in between.

Higher voltages = higher temps and higher noise. AMD supply lower ASIC's higher default voltage because they are more likley to need it to run stable at stock clocks. This reduces the chances of overclocking. High ASIS do not guarantee good overclocks, and low ASIC's do not guarantee a poor overclocker, but the odds follow the percentage.

As for the MSI PE being poor, I fully agree. The box for the card is pure false advertising. To coin a phrase, it is mutton dressed as lamb. They should rename this card to the "MSI 7850 Mutton Edition", because it offers absolutely nothing over their standard card.

Balb0wa · 28 May 2012 at 11:51

well i like my msi power edition card, nice and cool and does 1200 on the core, more than happy, when they reach £150 il get another for crossfire.

No idea how to raise the voltage on it though, cant get gpu tweak to show the voltage, and afterburner has the power limit thing. hmmm