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The Radeon 7850 is an overclocking beast

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Well, I just tried a few runs of the Unigine Heaven benchmark on my video card at its default 1000MHz core out of curiosity. That thing sure heats up the card more than Skyrim. With my ambient temp at 28C, the card idles at 35C with my fan speed set by me at a constant 40%. Playing Skyrim for an hour brings the temp up to 44-45C. Heaven heats up the card to 63-64C. If I set the fan to auto instead, fan speed goes up to 46-47% and the temp reaches the same 63-64C. I ran Heaven at 1600x1200 windowed so I could keep an eye on my temp (don't want to break my card) at the same time.

Here were the settings I used, FPS went down as low as mid-twenties, worst at the beginning in the stone-paved street of the village:

UsXKh.jpg


I may want to try overclocking the card just to see what its limits are. Default voltage only however. Card is said to be bios-limited to 1050 according to reviews but the HIS iTurbo software seems to go higher (1500, except maybe it has no effect past 1050, I'll see.)

How many runs of Heaven are needed before I can deem a certain speed stable enough? One hour (convenient time since I can get that going while watching the news on TV)?
 
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Today returned the Sapphire 7770, picked up the sapphire 7850 2gb overclocking edition. Double the price and hopefully close to a double increase in performance.

The Sapphire card is clocked at 920 GHz. How high can this overclock on stock voltage? The 7770 model cut off at 1125/1400.
 
Isura said:
Today returned the Sapphire 7770, picked up the sapphire 7850 2gb overclocking edition. Double the price and hopefully close to a double increase in performance.

The Sapphire card is clocked at 920 GHz. How high can this overclock on stock voltage? The 7770 model cut off at 1125/1400.
Click to expand...
Mine hits 1180mhz on stock volts and it's not a very good chip. I've settled at 1125mhz at 1.125v.
 
Card just went flawlessly through 1h of Heaven at 1050MHz, then one hour at 1100MHz core. Not touching RAM speed yet. Default voltage, fan speed constant 40%. Ambient temp 28C, idle 35-36C, full load 65-66C, so it looks like every 50Mhz adds about one extra degree Celsius.

it would appear like the 1050MHz core bios limitation mentioned in reviews is not there. I used the iTurbo overclocking software that came with the card and it works past 1050. 🙂

Edit: I just used GPU-Z to check the voltage during a Heaven run. VDCC (must be that one) indicates 1.210 is the load default for this card.
 
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Most cards cap out at 1.225 or 1.25 vcore, its a bios limitation.

I know my sapphire OC 7850 maxed out 1.225 and so i couldn't squeeze above 1.25ghz from it.
 
SickBeast said:
Mine hits 1180mhz on stock volts and it's not a very good chip. I've settled at 1125mhz at 1.125v.
Click to expand...

I got mine up to 1200/5600 on stock voltage. However the peak voltage is 1.21v, and when I use the Sapphire overclocking tool the voltage stays fixed (no power saving) when idle. Using Catalyst the voltage drops to 0.85v idle. What tool are you using?
 
My card froze & reset within seconds in Heaven at 1200MHz but was very happy at 1152 and I also played Skyrim for a couple of hours at 1152 without problems. Still at default voltage and 40% fan speed. Skyrim temp reaches 46C only, 18C above ambient and Heaven 66C. Only Skyrim setting not at ultra is shadows. With it at ultra, FPS in the worst spots of Solitude/Whiterun can dip to 36, at high it dips only to 47 at night. Otherwise FRAPS shows the 'Skyrim 60' pretty much everywhere.

May try to overclock the memory a bit in the next couple of days. As for the core, not gonna bother trying to find if there are more MHz above 1152, e.g. 1175. 1152 is a one-third overclock, average for that card at default voltage, and I'm downright happy with that.
 
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OK. Just ran Heaven for 1/2h with the VRAM at 1400 and no problem. Not gonna try higher. That seems like a nice number.

Final results I'm settling at, if someone wants to update the o/c database:

HIS 7850 IceQ X Turbo
Core: 1125 MHz
VRAM: 1400 MHz
Voltage: 1.210 (default)
Ambient temp: 27C
Fan speed: user-defined, constant 40%
Full load (Unigine Heaven) temp: 66C

b70.png


My little (9.4") card should be performing close to a default 7870 in Skyrim (AnandTech GPU bench shows a difference of 11-12% at 1920x1200) at those settings, so I'm happy. 🙂

Edit: card can play Skyrim & run the Heaven video many times without problem at 1150 core but the benchmark crashed near the end just now, so I downthrottled the core to 1125 and it benches OK now. Changed the results above accordingly.

WMbmg.jpg


Will run the benchmark a few more times to make sure it's stable.

Edit 2: Just ran 15 instances of the Heaven benchmark at 1125 without problems. 🙂

Now that I've tested its stable limit, the card is back to its default 1000/1200 as I don't need the extra speed for Skyrim.
 
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Isura said:
I got mine up to 1200/5600 on stock voltage. However the peak voltage is 1.21v, and when I use the Sapphire overclocking tool the voltage stays fixed (no power saving) when idle. Using Catalyst the voltage drops to 0.85v idle. What tool are you using?
Click to expand...
I'm using MSI Afterburner but I've also had success with Asus GPU Tweak.
 
I just got a XFX 7850 Double Dissipation Black Edition. Only benched with 3DMark11 so far. Here's what I got:

Stock VDDC: 1.213V (also the max allowable by TriXX)
Black Edition stock 975/1250 @ 1.213V.....................................5718 (CCC 12.8)
Black Edition OCed 1204/1505 @ 1.213V (+20 powertune)............6852 (CCC 12.8)

I found that 1200/1400 scores lower than 1200/1350 (6674 vs. 6744)...I assumed this was due to the clock ratios being being less perfectly divisible at 1200/1400. This was how I came up with 1204/1505...1204*1.25=1505.

Where is this OC database that I saw mentioned in this thread?

and if anyone can tell me, what's the highest anyone has pushed their 7850? This thread is TL;DR for me to sift through...

EDIT: My ASIC quality is 71% if that means anything
 
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etamin said:
I just got a XFX 7850 Double Dissipation Black Edition. Only benched with 3DMark11 so far. Here's what I got:

Stock VDDC: 1.213V (also the max allowable by TriXX)
Black Edition stock 975/1250 @ 1.213V.....................................5718 (CCC 12.8)
Black Edition OCed 1204/1505 @ 1.213V (+20 powertune)............6852 (CCC 12.8)

I found that 1200/1400 scores lower than 1200/1350 (6674 vs. 6744)...I assumed this was due to the clock ratios being being less perfectly divisible at 1200/1400. This was how I came up with 1204/1505...1204*1.25=1505.

Where is this OC database that I saw mentioned in this thread?

and if anyone can tell me, what's the highest anyone has pushed their 7850? This thread is TL;DR for me to sift through...
Click to expand...

Those are some good numbers man. How much does the CPU affect your score in 3Dmark11? What kind of CPU are you running?
 
Face2Face said:
Those are some good numbers man. How much does the CPU affect your score in 3Dmark11? What kind of CPU are you running?
Click to expand...

hmm, I wasn't able to find a place to add a sig in the usercp...so here's the list:

Lian Li PC-A71F
i7-960 (running stock, 4.1GHz max OC benched)
EVGA X58 Classified E760
Corsair Hydro H70 with 2x Lian Li fans
XFX Radeon R7850 Double Dissipation Black Edition
Asus Xonar Essence STX
3 x 2GB Crucial Ballistix Tracer DDR3 1600
2 x 300GB WD Velociraptor 300GB ea. in RAID 1
2TB Hitachi Deskstar 7K3000
Seasonic X750 Gold

All the benching for my 7850 has been done with stock CPU clocks. Here is the 3DMark11 page. btw, 5 of those scores in the orange bar in the chart are mine as I was testing different clock combinations.

Here is my old HD 5870 score with the i7-960 OCed. The 5870 is pushed to the CCC limit of 900/1300 and even the stock 7850 Black Edition is 25% faster than that. With the Black Edition OCed, it is literally 50% faster.
 
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Nice setup. I was wondering because my 7950 at stock clocks pulls a 6500 and some change. Overclocked to 1050/1400 it runs around 7800 I think. It's been a couple days since I ran it. I assume my Phenom II is holding back the 3Dmark11 score. Anyway, don't want to get to much off topic. Nice scores though.
 
hmm 1050 to 1200 sounds like a big jump. I think as cards reach max OC, it's not about temperature anymore but some kind of stability thing going on. When I attempt higher OC's the card crashes between temps rise.

Edit: Unless the card is crashing because of a non-monitored part getting too hot.
 
etamin said:
hmm 1050 to 1200 sounds like a big jump. I think as cards reach max OC, it's not about temperature anymore but some kind of stability thing going on. When I attempt higher OC's the card crashes between temps rise.

Edit: Unless the card is crashing because of a non-monitored part getting too hot.
Click to expand...

Yeah the TF3 from what Ive heard is only good for 1100 to 1150 core (open case) on the 7950. I would need to get this http://www.newegg.com/Product/Produc...82E16835186064 (Not anytime soon a lot of $$$) in order to reach 1200 or more. I have the 7970 PCB with the 6+8 pin ASIC of 89% and feed it 1.25 volts and see what I can get. I can hope though....
 
Got my Sapphire 7850 OC up to 1200/5600 on stock voltages using Trixx utility. Stable on OCCT, 3dMark, and Heaven. Modified the fan profile to be more aggressive over 50C. Stays under 60C on all these stress tests.
 
Isura said:
Got my Sapphire 7850 OC up to 1200/5600 on stock voltages using Trixx utility. Stable on OCCT, 3dMark, and Heaven. Modified the fan profile to be more aggressive over 50C. Stays under 60C on all these stress tests.
Click to expand...

What are you scoring in 3DMark11? and what voltage is it at? My guess is your stock voltage is the max voltage. Also for the hell of it, what ASIC quality rating do you have?

You should also rrerun 3DMark11 at 1200/1350. I scored higher with that than 1200/1400...maybe a ratio optimizing kind of thing.
 
etamin said:
What are you scoring in 3DMark11? and what voltage is it at? My guess is your stock voltage is the max voltage. Also for the hell of it, what ASIC quality rating do you have?

You should also rrerun 3DMark11 at 1200/1350. I scored higher with that than 1200/1400...maybe a ratio optimizing kind of thing.
Click to expand...

Scored 6800, 6750 on graphics. The max voltage is about 1.21v. ASIC score 72% from gpu-z.

I will try the lower ram speeds. I don't notice a big difference going from 1250 to 1400 anyways.
 
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