How to overclock a 7850 past 1050MHz?

[Freddie1980]

I've RMA'd my PSU (AX850] due to coil whine and thought I'd try out my old 850w Antec. Before I struggled to over clock my 7850 past 1150mhz at max voltage (1225mV). With my old Antec I was able to get 1200mhz easily at 1190mV. I guess there was more that was wrong with the AX850 than just the coil whine?

Damn I've just bought an AX650 I hope yours is a one off and those dodgy coils aren't plaguing all of Corsairs PSU's.

 

[Piklar]

My card works again! It is not dead, but something very strange happened to it.

I tested within a friends system, who also owns a 7850. When inserted on it's own, his motherboard will not post (same as mine), but when installed in crossfire as the secondary card it works absolutely fine. Corissfue runs flawlessly with expected fps increases and is reported correctly within CCC. However, when the card is used as the primary adapter (montior cables connected and in PCI-E #1), nothing happens.

Conclusion: ASUS GPU Tweak and GPU-Z somehow combined to corrupt my BIOS in a way that has made the card "half-dead". I now need to order a second 7850 so that I can get full use out of the other within an SLI setup.

Atleast I know the hardware is absolutely fine. It's just that the card does not report itself to PC BIOS correctly upon startup.

Thats excellent news, now the challenge is to figure out how to get it running on its own so selling it is an option down the line? Ive read youve tried many different bioses to fix the issue so am at a loss for suggestions as it appears your issue is possibly unique, however I wouldnt factor out blind luck for example you may be able to "re learn" the card/bios just by swapping it about or letting it run for a period as the 2nd card in crossfire it may just come right on its own.
Speaking from experience with crossfire hd7850s running 24/7 @1150/[email protected] the performance you get will be better than any single gpu card on the market right now especialy when play in eyefinity!!

 

[pieman109]

Thats excellent news, now the challenge is to figure out how to get it running on its own so selling it is an option down the line? Ive read youve tried many different bioses to fix the issue so am at a loss for suggestions as it appears your issue is possibly unique, however I wouldnt factor out blind luck for example you may be able to "re learn" the card/bios just by swapping it about or letting it run for a period as the 2nd card in crossfire it may just come right on its own.
Speaking from experience with crossfire hd7850s running 24/7 @1150/[email protected] the performance you get will be better than any single gpu card on the market right now especialy when play in eyefinity!!

What problems, if any, have you had with that Xfire setup?

 

[Piklar]

What problems, if any, have you had with that Xfire setup?

None! Have had these for almost four weeks and havnt had any.
They appear to scale extremely well especialy compared to the crossfire 5850s I had before these.
The process of tweaking the cards for 24/7 use and 100% stability in gaming has been the most time consuming part but fortunately worth the time spent.
After using Asus Tweak, CCC and Trixx I Prefer Trixx which is set to load at startup and sorts the fan speeds out as well so dont think about the clocks anymore, just play. The final part was getting the voltages right so both cards are 100% reliable..

 

[555BUK]

Cossfire 7850's are approx 30% faster than a single 7970 according the the few benchmarks I have seen. As costs for both systems are almost identical, and as both crossfire and sli are very reliable nowadays, it certainly makes sense

Specs
Transistors: 2.8bn x2 (5.6bn) vs 4.31bn
Stream Processors: 1024 x2 (2048) vs 2048 - tie
ROP's: 32 x2 (64) vs 32 - 7850 win
Texture Units: 64 x2 (128) vs 128 - tie
Memory: 2GB x2 (duplicated 2GB) vs 3GB - 7970 win
Memory Bus: 256bits x2 (512bits) vs 384bits - 7850 win
Memory Bandwidth: 153.6Gbits x2 (307.2Gbits) vs 264Gbits - 7850 win
Power Consumption Max: 130W x2 (260W) vs 250W - 7970 slight win
Power Consumption Idle: 14W + 3W ZeroCore power (17W) vs 19W - 7850 slight win

There are however several good reasons to opt for a 7970. For multi-monitor setups the extra 1GB DDR5 may eventually come in handy. Also, some mobo's and cases can only handle a single card.

I do think that for the vast majority of people 2x 7850's will be a superior solution to the 7970 and the GTX680.

 

[Twirlywoos]

Dear God, OCUK have the HIS Ice Q @ £180, I'm tempted to go xfire.

A single 7850 performs really well and I'm extremely pleased, I planned to get a PhsyX GPU especially for Metro Last Light when it comes out next year.

Must Resist, if it was £150 it would be a no brainer and I'd get one straight away

 

[Ade74]

so does the HIS overclock as well as the Msi? or is it all down to silicon lottery?

can anyone with the his comment on noise levels and temps?

Had been thinking of getting the msi but the HIS one is £35 cheaper today

 

[Psymonkee]

Is the HIS card on special today worth it?

Would be upgrading from a 9800GT (don't laugh )

 

[wazza300]

Is the HIS card on special today worth it?

Would be upgrading from a 9800GT (don't laugh )

yes worth it,it will be mega fast compared to current card

 

[555BUK]

I think the consensus is that Sapphire and MSI have the best coolers, with HIS being a little behind but better than reference. The HIS cooker has just two small heatpipes and a relatively small heatsink. MSI has 3 small heatpipes and a larger heatsink, whilst Sapphire has two very large heatpipes and an MSI sized heatsink.

I personally would go for a Sapphire non-overclock edition because they are generally good and cheapish to buy.

 

[Twirlywoos]

so does the HIS overclock as well as the Msi? or is it all down to silicon lottery?

can anyone with the his comment on noise levels and temps?

Had been thinking of getting the msi but the HIS one is £35 cheaper today

Overclocking the cards is all down to luck. A few members have had the sapphire and msi ones too that don't overclock to 1200.

But the HIS card I have overclocks fine. The noise and cooling is on par with all the others judging by the thread.

I think OCUK deal with any RMA issues for the Sapphire and HIS upto 2 years and the MSI is 3 years.

 

[Ade74]

Well i've ordered a HIS one, its due to arrive Tuesday.

 

[Twirlywoos]

Do you have Virtu enabled? That caused some weird juddering for me, both with my 7850 and GTX680.

"atiflash -p -f 0 backup.rom" should definately work. What error message do you get?

thanks that solved the flash issue. But my screen still judders, it maybe the mouse drivers. Gaming is fine but browsing is a tad annoying with the juddering.

 

[new boy]

I'm sure I'm being incredibly stupid, but how do you increase volts with trixx???

I've increased the "board power Li" which I presumed was what I was meant to use, but GPUz still reports the same VDDC (which I've presumed is voltage), and It makes no differnce to my stablility....

C'mon, put me out of my missery and get the spoon out lol.

Using Sapphire non-OC btw

 

[shawsy109]

Hey guys, Ive not really monitored this thread much, but currently i have a 6950, but i want more grunt to be honest. I would get a 2nd card but from what i read the 7850's are great little cards and oc like its going out of fashion.

Would you get a 2nd 6950 or pick up 2 of the iceq 7850's?

 

[RevBillyG]

I'm sure I'm being incredibly stupid, but how do you increase volts with trixx???

I've increased the "board power Li" which I presumed was what I was meant to use, but GPUz still reports the same VDDC (which I've presumed is voltage), and It makes no differnce to my stablility....

C'mon, put me out of my missery and get the spoon out lol.

Using Sapphire non-OC btw

Scroll down a bit further. It's beneath the board power line

 

[555BUK]

Hey guys, Ive not really monitored this thread much, but currently i have a 6950, but i want more grunt to be honest. I would get a 2nd card but from what i read the 7850's are great little cards and oc like its going out of fashion.

Would you get a 2nd 6950 or pick up 2 of the iceq 7850's?

A second 6950 will be much cheaper and offer almost the same performance. 6950's can be picked up on the MM for ~£120.

 

[shawsy109]

A second 6950 will be much cheaper and offer almost the same performance. 6950's can be picked up on the MM for ~£120.

Cant get on MM mate, not enough posts yet. Im after a particular 6950 to, the ICEQ with the same cooler as the 6970 ICEQ, ocuk just went out of stock. I sent a email and posted in pre sale forum to see if they might get one, or have a spare laying about lol.

 

[Twirlywoos]

Hey guys, Ive not really monitored this thread much, but currently i have a 6950, but i want more grunt to be honest. I would get a 2nd card but from what i read the 7850's are great little cards and oc like its going out of fashion.

Would you get a 2nd 6950 or pick up 2 of the iceq 7850's?

Personally I would be upgrading to a card with a larger performance gap if coming from the 6950/70. The performance difference is marginal unless you're wanting a card on newer architecture, uses one 6 pin power connector and is quieter.

 

[ussff]

Will cf with two sapphire 7850's oc'd run 3x 24" Dell mons in portrait 3600x1920 with enough grunt on BF3 or should I opt for a future proof setup and go 7950/70 and have the spare slot for the future?

I only ask cos I have a thermalright twin 6 pin GPU psu and it will feed the CF 7850's real nice at the best bang for buck - but the upgrade path means starting again if I get th 7850's...