Sapphire 7970 OC max OC...

Well are you using solid software like MSI Afterburner to do your overclocking? Is your power supply able to handle everything?

If the answer to both of the above is yes, have you tried increasing the core voltage a bit and making sure your power target is at +20?

What sort of tests are you doing that it's crashing?

I'm using Sapphire Trixx, and I'm fairly certain my PSU is good enough. Powertune is at +20. Mainly tested in Crysis 2 and Battlefield 3.

Hmmm.... well, at that point you should be trying small (~10-25mV) voltage bumps and seeing if that gets you stable. Keep a close watch on your temperatures when increasing voltage.

(I'm assuming you're sure the crashes are related to the OC in those games).

And it's always possible you got a dud card... I'd consider any 7970 that wouldn't hit at least 1100 MHz a dud for overclocking.

It does have 2 Bios settings, the default one and one clocked at 1100/5000 or something. When I switch to the OC'd one, I get frames that are unplayable, which is odd. Could there be something wrong with my card?

Yup that sounds like something is wrong... if your PSU is fine then you should probably warranty/RMA your card.

I'm currently getting 100-110 FPS in Dota... I used to get 118-120 (capped at 120) on my 6870. Sigh -_-

Sounds like either a card issue, but it does also seem like a PSU issue. Tell us your PSU, we've had people saying their PSU is good enough but are really just advertised as 1000W with only like 250W on the 12V rail.

NONONO! Eish you are not raising the cards voltage, you are just raising the max power allowed TO THE CARD.

Use MSI afterburner to increase voltage by 20mV at a time!
Then raising Clock and stresstesting. Raise clock and test until you lose stability.
Raise mV again and continue process until you reach desired OC or unacceptable temps.

Uh, an Antec Earthwatts 650w, or something similar.




Do I really need to though? It's at 950mhz, and I just want to raise it to 1050 or something for now. Surely the default voltage is enough for that? People seem to say that most 7970's can reach 1150 or so without a voltage increase :\

Where did you hear that? Every chip is different. Increase the voltage or leave it below 1050MHz

Is there an easy way to stress my GPU after each overclock? I was going into Crysis 2 and playing for a bit, but that was a bit tedious.

Easiest way to get a preliminary test of your OC, IMO, is to run a couple loops of Unigine Heaven + 3dmark11 performance preset.

That doesn't guarantee stability, but it's a good enough check that once a clock can pass that, you know that the worst case scenario is that you have to do some minor tweaking (add a couple mV of voltage or step back clocks 5-20 MHz) if it starts crashing in a game.

Power at +20 is where it should be for overclocking. You can always turn it down later, but while you're trying to find what overclocks your card can handle it's best to have it at +20.

Out of curiousity, what is the default voltage of your GPU (you may need to use Afterburner to find that out)? The reason I ask is that there are 3 different stock voltages possible for 7970s... some of them are 1.17V, some are 1.112V, and some are 1.08V (pretty sure my memory is correct on those marks).

It is common for 7970s to hit 1100-1150 MHz on the core with stock voltage, but it's never a guarantee. I'd still recommend an RMA/warranty replacement of your card since the secondary BIOS doesn't work.

Stock voltage is 1175. I'll try the second bios again once more tomorrow or something to make sure it isn't working, before I go off and replace it. Overclocking it a bit, letting it run in Unigine for a while, then doing the benchmark for 30 seconds and seeing the frame rate. It is going up, which makes me happy.

In my (limited) experience of having gone through 3 different 7970s and overclocked each one to its limit, chips with a 1.175 stock voltage overclock more poorly than chips with one of the lower stock voltages.

You probably just didn't manage to win the silicon lottery on that card  

Would all Sapphire 7970's be the same voltage?

Also, I've got it up to 1050 now and it's running fine through the Unigine benchmark... though it did crash after about half an hour of Dota 2 at 1025 :\

Nope the stock voltage just depends on the chip, not which card you have or which brand, as far as I can tell.

Okay, so it's going quite well... but it finally crashed, meaning I need more volts, right? Raise by 20 each time? How do I know when to stop raising the volts though? I don't want to put too many in and kill it :\

Use Unique Heaven benchmark.
Or 3d mark 11

Yeah, it's definitely going back. The second bios definitely does not work at all, and the first bios cannot handle any kind of overclock. Sigh, the place is an hour away.

That sucks, but unfortunately this sorta thing happens every once in a while  

Before I make the trip, is there any chance it could be my fault? The OC works for a little bit, but then it always freezes my PC. I upped the voltage a bit, but it did nothing. The second bios either has a low framerate, or freezes in games. I'd hate to get another just for the same outcome.

Well without testing it in another PC there's no way to know 100% for sure, but it's very likely that it's the card that is the problem. If you have another PC around that you can test it in, that would be worth doing.

Whats the problem? Just pump up the voltage to 1.2v and monitor temps!!

if your 2nd bios crashes then you definately got a bad card. id RMA that asap. i have the exact card running in 2nd bios and it works flawlessy. i left core at 1k mhz but up memory to 1500 and it has passed furmark easily.

I did. It crashed in about 30 seconds.

Got a new card, same model. Clocks SEEM to be stable at 1040/1450, which isn't that high but I guess it's just the luck of the draw?

wow that's some crappy luck right there.... does your secondary BIOS at least work this time?

Yeah, second BIOS is working. Haven't played for more than maybe 5-10 minutes, so I can't even tell if 1040 is stable.

I have a slow green HDD that has about 1.6TB of data installed on it over the past year, it has slowed down my system. Could this affect the GPU at all? Whether the OC or the frame rate? Tempted to do a reinstall now...

A slow HDD should have nothing to do with your OC and very little to do with your performance in games outside of loading times.

If your secondary BIOS works, why not just use that to run the card at 1100 MHz and then overclock from there if you want more performance?

That's what I did, which managed to get it to 1040 :\

Ohhhhhhhhhh I thought you said the secondary BIOS was an 1100 MHz BIOS.

Anyways they may just be binning all the crap chips to that card now, which could explain your bad luck. You can always try increasing the voltages  

The card should still handle most everything at 1040... throw a little bit of a memory overclock on there and it will be a little faster overall than a stock GHz edition card.

Last question (most likely! I'm sorry!)... is this a good score?

http://www.3dmark.com/3dm11/5563083

Looks like more or less what I'd expect from a stock GHz edition card + stock 3570k. Maybe a bit low, but nothing to be worried about.

Got a little over 10k by switching to BIOS 1. Performance is great now, not as good as others I'm sure, but still great. Though Battlefield 3 seems to have a lower minimum FPS now... I'll out that down to beta drivers.