I think I can achieve 9000+ once the official driver is out. Every time I try to overclock beyond normal threshold, it restarts my iMac. So far it's 28% faster than 680M by any means, it might be possible to push up to 9700.
I managed to achieve 1170mhz (100% stable) with my Retina Macbook Pro (650m), using the same method.
hi When I am playing Crysis 3 (The only game I have at the moment) Love it
I have a Temp around 84c-86c on GTX 680MX
When I have it overclock to 200/250 I have the same temps.. start to wondering, is that possible? little scarred about the high temps.
When I have it overclock (MSI Afterburner) I have also the fans via lubbos set to minimum fan speed 1200rpm and max to 2100rpm, Have also tried to sett it to 2500 but it sounds to mutch I think hehe..and is it Normal that lubbos direct go upp to my max settings (2100) when I click apply?
My i5 CPU is around 80c-85c MAX is thats normal? I have also Disable the turbo like Mac32s advice (no different on my iMac)
I have play Crysis 3, 3-4 hours everyday and it works great overclock! no problem at all, no rebooting. just worry about the temps..
sorry for my Englishand all the questions..
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Hi bd,
I have the 3.4ghz i7 CPU (which is hotter during load than the i5), and my CPU temp is now at max 76-77C when playing Crysis 3. GPU max at 79-80C. This is 680mx overclocked to +250/+375. I set the fan speed at 2500rpm, and just use headphones. Then you don't notice the fan noise very much.
You turned off CPU turbo mode by setting max CPU speed to 99% (advanced power options in control panel), right?
Playing older or less demanding games now (like Crysis 1, Alan Wake etc.) gives very manageble temps, the CPU temps are in the high 60s.
Regarding your temperatures, I'm not an expert in that area. However, I think you should turn up the fan to 2500rpm all the time when playing Crysis 3. In a closed system like the iMac very high CPU and GPU temperatures could affect other components. Do you have a regular hard drive or SSD? Make sure your hard drive is not hitting 60c, hard drives are extra susceptible to high temperatures. 80c is normal for a GPU at full load (Crysis 3), but personally I'm uncomfortable with going beyond 80c in an iMac.
Alan Wake is a very demanding game, even by today's standards. I have to turn down a ton of settings on my iMac to get the frame-rate up, especially in 1440p.
Could one of you please dump the GTX680MX videoBIOS with nvflash and upload it here:
From a native Windows install:
Download NVFlash 5.118 for Windows | techPowerUp
Just run in commad prompt (cmd)
nvflash -b GTX680MX.ROM
or from a bootable DOS USB stick:
http://www.techpowerup.com/downloads/2165/NVFlash_5.127.html
Thank You very much!![]()
Thanks MAC32 for your time and answer
Yes I turned off CPU turbo mode by setting max CPU speed to 99%, how can it be possible that i have 80c-81c on CPU just i5? you think the disable CPU turbo have better effect on i7?
I have a 1TB Fusion drive. thanks will check the temp on the HDD.
Your GPU max at 79-80C how can that be? when I have 84c-86c when its not overclock? and when overclock to 200/250 its around same for me...is it the the fan speed? most try on 2500RPM time to pick up my old headphones![]()
Hi there! Man, I'm spending way too much time playing computer games after I got my iMac. The 680mx kicks butt.
It's definately the fan speed. I did notice my GPU got up to 80-81 after playing Crysis3 for several hours, but that's at +200/+300 and +250/+375 (hardly any temp difference between those overclocks). Now playing STALKER with Complete addon at +285/+425 100% stable, nice game!
Just download Lubbos fan speed controller, then set your fans to 2500rpm and enjoy.![]()
Pretty nice that disabling CPU turbo boost also gives a higher stable GPU overclock, at least for the i7 CPU.
Be careful with those overclocks. You can hear the capacitors straining (coil whine) if you put your ear to the back of the iMac with those kinds of clocks. I don't know if the coil whine is bad in the long term, but it's definitely there. Tough to hear over the sound of the fans, but before they ramp up - you can hear it.
Hm, could you describe this coil whine? I'm not hearing any difference in sound from my iMac gaming/overclocking or not. I turned down the fan speed, and even tried a couple of different games and overclocking settings.
@Mac32 yeh same her, have gaming more this week then all last year
what is the temp for you in Crysis 3 with no overclock, normal fan speed and no disable turbo bost?
@WilliamG are you sure its not a cable or something touching the fan? I had it to and I have heard more people have it... someone was saying try to tilt the iMac to the side and it will go away... It work for me..![]()
Yeah, WilliamG, sounds like a cable slightly hitting the fan blade. Doesn't coil whine sound more like a high pitched even tone? Anyhow, not hearing anything different soundwise overclocking or not. Think I'm gonna continue to overclock the 680mx, it makes a big difference in framerate.
Going from only using laptops for 6 years, to gaming on a beautiful 27'' screen is pretty awesome.
Bulldog, I strongly advise against gaming with normal fan speed. Just accept some fan noise, and use a headset. Your roommates/neighbours will thank you also.![]()
ahh if its go away when alt-tab then its not the clicking from the cable...
so mid-80c is full normal on the new imac then?
What have you the rpm on in lubbos when gaming?
For the GPU, yes. Anything under 90C is good enough for me. Not really reasonable to expect much less when slamming the GPU.
I don't use Lubbos. Not seen a reason to...
I don't use Lubbos. Not seen a reason to...
Hope you don't have any overclock!!!