Overclocking a 7850

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Gilbert_pwns

Gawd
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Nov 13, 2010
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I just got an xfx 7850 1gb black edition and I've heard that I can overclock it to make it perform as well as a 7870. I was wondering if anyone has experience overclocking gpus and particularly overclocking these cards. Not sure which program to use.
 
Which exact XFX 7850 model is it? In particular, the cooling solution.

7850s generally run pretty cool, but if your XFX card is one of those with a non-heatpipe cooler you won't get very far.

I've got 2 7850s (HiS / Sapph), and both do 1200/1350 @ 1.25v. Temps in the mid 60s C.
 
5 things you can use
Catalyst control center
AMD gpu clocking tool
Asus GPU Tweak
MSI Afterburner
Sapphire Trixx

I like both Afterburner and Trixx, Trixx is a bit less clunky IMHO but afterburner has stuff that Trixx does not if you know how to use it.
You do want to make sure you adjust your cooling fan, I like to keep mine 75c or below gaming loaded which is usually 50-65% fan speed better to control it yourself and always have it spinning a certain % its easier on the ears and the fan.

I do have experience overclocking GPU however every GPU clocks differently, generally you want to start by overclocking the core clock first, generally its advised clock it up by 10Mhz or so at a time till it becomes unstable or you are happy with its performance, when testing you can use something like your favorite game(s) as not all games load up the same, usually when it starts crashing after a bit of being loaded its not stable and you can give it extra voltage if you like just a small bump if you do don't go crazy as voltage and heat kills things.

Overclock the memory in a similar fashion 10mhz or so at a time, when the memory is being pushed to hard usually you end up with less performance with current cards as it "fixes" itself through error checking and so loses performance in the process that and between memory and not enough voltage you usually get artifacting so this tells you if pushing to hard.

I play BF3, Diablo III, World of tanks, as again every game loads differently so some like Diablo III in my case could get away with a higher core clock before crashing where BF3 higher memory clock there is a happy medium generally speaking if you just want performance and are happy with the settings the core clock alone is fine and usually can go higher if memory is not clocked as high, if you like using Anti-aliasing and such then memory clock is very usefull as with Radeons many of the "quality" settings are done via memory as well as core, so it just to find the balance for whatever games it is you like playing, that and the memory is quite fast to begin with so not a massive performance jump to clock memory up like it is to clock the core up as the core is the clock for the shaders as well.

Anyways, little at a time and test Heaven DX11 is a good test as well and you can let it run with different settings to stress test the card generally speaking if Heaven DX11 crashes it will in game as well, if it does 2 or more passes in Heaven without issue its usually good to go in a game.

Hope this has helped answer your questions, just an FYI for a 7850 to match a 7870 performance wise you need at least 1250 on the core with memory stock speed which is 4800 or 1200 depending on how you look at it, for it to be a match in regards to pixel fill rate which only generally matter with older games far as I know as it scales according to clock speeds as both the 7850 and 7870 have the same number of ROPs and pixel fill rate is rops x core clock speed, 7850 has less shaders so needs to clock higher to match the raw performance base line of 7870, I think it was somewhere in the 1175 range to be near parity.
http://www.gpureview.com/show_cards.php?card1=678&card2=677#

Just an FYI 1 of my 7870s could do 1175 1425 core/memory before having issues, my other well it clocks like a mad man easily 1250+ and 1500+ so it all depends. Average overclock of 7850 if I recall was in the 1180 1450 range with a slight voltage bump for stability this allows some to push 1200 on the core but most will do 1170+ you may have to allow unofficial overclocking in Afterburner to do this though.

Anyways best of luck and remember voltage and heat kills a card, don't play with voltage and its way less likely.
 
Get Trixx, my MSI 7850 wouldn't go past 1050MHz with anything other than Sapphire Trixx.
 
Im pretty wary of any voltage changes. on Trixx it says the VDDC is at 1138 on stock. Not sure if I should touch that.
 
small bumps don't kill anything large ones will, for example 1219 is stock voltage on 7870, I ran mine at 1262 for 1 1/2 yrs(since release anyways) in an overclocked state at max stable clocks(1218/1425) gaming, bitcoin mining, stress testing etc at 62-70% fan temps 64-76c(dual card for a bit and summer temps) max is 1300 and it was fine granted it was/is a very good cooler that cools all of the card Vreg included. A small bump i.e 1 or 2 notches is very unlikely to kill the card, but anything is possible just as the card could just up and die for no reason by turning on the computer 1 day.

Anyways, with afterburner you would have to enable unofficial overclocking which will allow more range for overclocking at least it should unless it was hardcoded in the bios to never surpass x which I do not believe any are, the only other way around this(and Trixx would still face the same limitation in this case) would be AMD Gpu clock tool, or Radeon Bios editior and I would highly recommend against bios editor as it is quite easy to brick your card and hard to fix if you do not have another gpu to reflash it back to factory defaults (I have done this before lol)

Anyways unofficial overclocking in afterburner, sapphire trixx or AMD GPU clock tool, though as far as I recall to use the clock tool one you cannot control fan speeds. Voltage wise it is the same exact chip as the 7870 the difference is it has less shaders and TMU as AMD during testing found it didn't match up to specs so "cut" part of the core and so it needs less volts to run at "factory" speeds.

If you go looking many threads folks state of running them at 1.25v and some even at 1.3v for bench runs, generally it either works and could use the extra volts or it doesn't no matter what speed you try to run it at, again all chips are different some chips are low leakage so don't require as much volts but usually cannot be overvolted to help as much as the high leakage chips which require the volts but also get hotter and in turn can usually outpace the low leakage ones.

Yours like many others at stock factory settings is 1.138v so a couple bumps is very unlikely to kill the card, just watch the temps that is very important, stock voltage for 7850 from AMD reference is ~1.08-1.138v so yours should hit decent clocks with something that allows the higher clocks, the upper end of many I have seen is 1.25v 1320 1540 core/mem average seems to be 1.225 v 1215 1435 core/mem in both cases temps seem in the 68c loaded range at these settings, so it really depends, you may have a great card that overclocks like crazy, you may not, I wouldn`t be concerned about bumping volts 1 or 2 notches if you need to, but of course try getting as far as you want or comfortable with first, core speed then memory speed then both.

For my 4870, 6870 and 7870s if jump core speed it limited memory speed if up memory then core was limited(though not as much) overall it was the core speed that mattered more I would say in my experience at minimum 80+% of the time, but it is a good habit I suppose that if core runs faster memory should as well :p
 
look at it this way, less stock voltage but less shaders and such to run, so can usually clock higher and need less volts to do so, can also usually hit a higher clock at stock voltages. AMD knew people would overclock them as dis Asus, MSI, Sapphire etc they do have a margin in there to account for this, a couple bumps for pretty much anything is not going to kill it, redline the rpm, temps, and hp however well that usually makes the engine die lol
 
I can't figure out how to read the VDDC and I don't want to play with it.

Does 1138 mean 1.138 v?
 
Gilbert_pwns said:
I can't figure out how to read the VDDC and I don't want to play with it.

Does 1138 mean 1.138 v?
Click to expand...

Yes. I believe that the default for the stock clocked 860MHz 7850 is 1.075V.

My MSI 7850 came with a factory overclock of all of 40MHz (900MHz) and the default voltage is 1.138V which is probably much much much higher than it needs to be. If you don't feel comfortable upping the voltage, leave the voltage at the default and increase your core gpu clock as high as you can at the default voltage without losing stability.

Right now I have my two 7850s in crossfire at 1150MHz at 1.170V. That might be more voltage than they need though. I haven't had time to fine tune my overclocks.
 
JapaneseGorilla said:
Yes. I believe that the default for the stock clocked 860MHz 7850 is 1.075V.

My MSI 7850 came with a factory overclock of all of 40MHz (900MHz) and the default voltage is 1.138V which is probably much much much higher than it needs to be. If you don't feel comfortable upping the voltage, leave the voltage at the default and increase your core gpu clock as high as you can at the default voltage without losing stability.

Right now I have my two 7850s in crossfire at 1150MHz at 1.170V. That might be more voltage than they need though. I haven't had time to fine tune my overclocks.
Click to expand...

The memory on mine was OCed by default too. It seems to be unstable with anything over 1000 if I don't up the voltage.

Got it to 1150/1250 at 1.160v
 
worth is a opinion. I had 2 7870s for awhile and well not all game scale well, the ones that do some have issues, and to top it off the extra noise, power, and especially heat generated unless you have a nice roomy case and a properly slotted motherboard don't make it much worth it IMHO. Extra performance is nice for sure, but until AMD and even Nvidia in some cases figure out how to make 100% scaling (as in both cards share the workload 50-50 all the time) its a matter of opinion.

VDDA is core voltage, now then you did not answer the question someone else asked you, which is the exact card you have via model number this should help knowing or at least better gauging its limits a bit easier to know if it will have proper cooling and the like.

And if you do go crossfire, I know myself I will at some point again, however I will make sure 1 of them is a blower style fan(fan on one end of the card, maybe one of those HIS style coolers) for the card that gets less airflow as it can help to make sure the air is channeled properly, many of the dual fan cooler cool really well but they blow the air everywhere and have heard many times of 1 of the 2 cards being quite a bit hotter then the other, in my case the "sandwiched" card was at minimum 12c hotter(67-69c on one card 79-82c on the other card and fan was running at an annoying noise level) well unless you go liquid cooling but many of us just don't have that option, again just my opinion.

If you can do 1150+ on the core and 1350+ on the memory then you are doing good. 1138-1200 is perfectly fine or 1.138-1.2 however you want to look at it, for me I can devolt to .980 at stock speeds or max clock I need 1.23v for my current card. GCN cards have a huge range and they all have the same chip(7850/7870 is same, 7950/7970 is same they can use same voltages and "can" hit the same speeds provided cooling is good and proper voltages for the speeds is given) its all about balance.

You can always drop voltage to control temperatures as well to find a "sweet spot" as AMD and the other card makers do not test all cards 100% they just flat test to know that if voltage is x it will do approx. x power use and x temperatures at x fan speed etc, its a range is all, this is also why the voltage ranges are so huge and why in this case yours is locked to below a certain speed/voltage otherwise it becomes faster then a stock 7870 which isn't good for business, this is also why we have special overclocking tools that can bypass this soft coded limit.

I do not know or have heard of anyone killing their 7000 series cards yet, they made them really well, and have god components on them, maybe some like HIS or XFX might cheap out on some models but generally they (radeons) are built very well.
 
4th picture down
http://www.softpedia.com/progScreenshots/SAPPHIRE-TriXX-Screenshot-215404.html
says core voltage
for afterburner it also says core voltage(mV)
if you use something like openhardwaremonitor it shows as core voltage but also shows as 1.219 in my case stock voltage, where afterburner shows a full number 1219, hardwaremonitor however does not show it running at the lower specified voltage as soon as you change any clock or any voltage it just reads the "default" but you can tell its working from temperatures given and with afterburner it has a nice graph to show the change as well, I also power monitored it with a kill-a-watt and it does in fact boost or lower power use, memory does a pretty large amount as well for some reason.
 
Gilbert_pwns said:
BTW

Is it worth getting two 7850's to crossfire? I'm thinking getting another one next month or so.
Click to expand...

I have two 7850s and crossfire has worked perfectly for me so far. However, I've only played a few games so far (battlefield 4, battlefield 3, dota 2).

So I believe that for the price, two 7850s in crossfire offer amazing bang for the buck, especially when you consider how easily you can get a 30% overclock out of them.

The only problem in your situation is that you have a 1gb 7850. I'm worried that you might end up being very VRAM limited. Others might have more to say about this point.
 
JapaneseGorilla said:
I have two 7850s and crossfire has worked perfectly for me so far. However, I've only played a few games so far (battlefield 4, battlefield 3, dota 2).

So I believe that for the price, two 7850s in crossfire offer amazing bang for the buck, especially when you consider how easily you can get a 30% overclock out of them.

The only problem in your situation is that you have a 1gb 7850. I'm worried that you might end up being very VRAM limited. Others might have more to say about this point.
Click to expand...

I only play at 1600x900 though so I don't think I needed 2-3gb.
 
well not all games use the same quality settings but yes reduced resolution helps of course, and in that fashion alone I highly doubt you could make use of CF 7850s at that low of resolution anyways unless you are wickedly pushing the quality settings and even then the ram limits will get in the way of efficiently pushing some of the settings.

As for the OC, step at a time, if was stable at 1170 with volts at 1138 and you tried 1175 with pushing volts that much higher then take more time to find the sweet spots. Most chips do have a "wall" in regards to the speeds they want to do and need a lot of volts to breach that wall, as stated most that were pushing 1200 or higher needed 1.2v range, so you can be happy with where you are, or take more time to find its sweet spots, 1180 volts should get you in that clock range but all cards are different, AMD gpu and cpu are quite reliant on the cooling as much or more then the voltage in itself.

So what speed did you reach so far core and memory and at what voltage?
 
lol lol. if you went that route why didn't you up it to a 280x? a 7850 overclocked is matching a 7870, a 7870 overclocked 95% of time easily beats a 7950, where a 280x/7970 is in a world its own.

So you returned it cause it didn't overclock as much as you liked? xd, ahh well, hope you enjoy this one, but there are better choices then the gigabyte one
 
dragonstongue said:
lol lol. if you went that route why didn't you up it to a 280x? a 7850 overclocked is matching a 7870, a 7870 overclocked 95% of time easily beats a 7950, where a 280x/7970 is in a world its own.

So you returned it cause it didn't overclock as much as you liked? xd, ahh well, hope you enjoy this one, but there are better choices then the gigabyte one
Click to expand...

I got it for 260. But yeah if I had paid 300 for it then I would have just gotten a 280x.
 
raghu78 said:
you could have got a sapphire hd 7950 for USD 210. 925 mhz, unlocked voltage and good cooler. gigabyte hd 7950 comes at 1000 mhz but locked voltage.if the order has not shipped i would suggest you cancel it.

http://www.newegg.com/Product/Product.aspx?Item=N82E16814202026
Click to expand...

I bought it at Fry's and don't mind the price too much. Mine was at 1000mhz default and I Oced it to 1100.

Only reason I would return it is to get a 280x but I'm not sure if the extra 80 bucks is worth it. I can play BF4 on ultra. I'll save the money for a better proc.

Oh btw the 260 was including California tax :p. The actual price is 242.
 
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