RedLionRisen

I'm noticing unusual throttling behavior when the gpu is being pushed to its limit, for the gpu and cpu, at otherwise below-throttling temps. Starting to wonder about the power consumption...

Awesome! Can't believe I didn't see this til today. I flashed my 650m with the basic 1.1 overvolt bios. Increased the core clock to about 1230 which passed 3dmark with the result below. However, it wasn't furmark stable. about halfway through the gpu hit 87 degrees and started to throttle down. Soon after, furmark and the gpu crashed, lol. I'm guessing 1210 is more the stability limit, which is still about 10% higher in core speed and benchmark performance. I've heard of most 750m ownersm overclocking to around 1250, and have heard of 650m owners doing over 1300 on other systems. I imagine the 750m owners have the slightest advantage there with an extra .03 volts (1.13 max). It seems to me that the performance scales linearly with the core clock increases, which is surprising, but the power consumption increases much faster as you up the core clock.

I still haven't tried it, lol. I need to get a laptop cooler to mitigate the temperature spike sure to come with the voltage settings of the 750m, assuming the flash works...

I might be willing to give it a try. If the BIOS for the 750m aren't compatible, then the flash will most likely fail during setup, right? I should still be able to flash the correct version if that happens... Only thing is, the 750m voltage is definitely higher than it needs to be, even for overclocking. Maybe it'd be possible to force an overclock on a lower p-state, with a lower voltage than the boost state.

Do you think it'd be possible to flash the 750m BIOS onto the 650m, and use the same voltage settings as the 750m?

Oh lord...

I guess we'll find out how similar they are after the voltage Bios come out, lol. But my bet is that they're much the same.

The fan blows in the same direction that the exhaust does I take it?

Haha, definitely not! I meant 1.13 volts. Here's one thread where it's mentioned: Lenovo Y400 Owners lounge - Page 18

Just a heads up: It looks as if the new 750m card (based on the same design/architecture) is set at 1100Mhz turbo @ 1.3volts. I assume the 650m should be able to operate right about the same range, so it might be a good starting point for when you modify the voltage in BIOS (maybe a little less even).

I can get my card up to 1110 Ghz fully stable in games.

Because you will never conceivably run anything that will put the computer under that kind of forced load? Running one burn test, much less two, only indicates the extreme maximum your system can handle. It's well beyond what you'd ever see in normal operation. Using that as a basis for claiming the sky will fall under normal usage isn't... correct. If you run a more reasonable assessment of the temperature response in the system and find it to be 95 max (for example), you should be able to expect the temperatures not to spike beyond that, certainly not to the boiling point. And even in the unlikely event that it does spike that high, the system will shut itself down before any damage occurs, and you will know to dial back the demands on your system. But in any case, if you're worried about it, definitely don't mess with it.

Hmm, your temperatures seem a little bit odd to me :/. I've run multiple full-load 3dmark, furmark, WEI, etc. tests, and done hours of gaming on my system with the gpu overclocked AND cpu on constant turbo mode, and the absolute highest I ever got out of my cpu was 92C, and 78C on the gpu during furmark (which is 8 degrees higher than I have ever seen it go in any other usage). No external fans used right now either, plus I'm running the smaller 14" Y400 model. All of that amounts to a rather large difference in cooling between our systems, and I'm not sure why yours seems to heat up that much. Maybe because you're running two gpus? Out of the bag, the cpu does run kinda hot for sure though. I regularly peak at 90C during gaming, but not a degree more. I'd prefer to keep the cpu under 95 at all possible times.

I figured as much. The person who said they ran the 650m at those settings (through a BIOS mod, so no frequent switching) said the gpu stayed below 86C. I wouldn't suggest EVERYBODY go overvolting their gpu, but it's certainly doable on these late generation platforms. Still, I'd only advise it with a good cooler (which I will be using). - - - Updated - - - I mean full performance use with the maximum state being at that voltage... But point taken. I'll probably need to be able to modify the BIOS myself to tune it to my machine and usage. I just wish I could figure out how its done, with the vbios being integrated into the system bios and everything.

Overvolting is perfectly safe, as octiceps alluded to, so long as you are able to intelligently monitor the system temperatures and gpu stability. It's like tuning an instrument. Each individual one is different, and has its own perfect balance. From what I've seen around the internet, the GT 650m has a great deal of overclocking headroom, with fairly linear performance increases. The stock maximum voltage of 1V allows you to overclock to about 1100Mhz, but I've seen people increase the voltage to about 1.1V, and stably raise the core clock to 1300Mhz, which does correspond to about a 15% increase in performance (by 3dmark standards) over the voltage limited clock of 1100Mhz. Compare that to all stock settings, and it would represent a 50% increase in performance (by benchmark standards of course). In my opinion, that's reason enough to modify the BIOS if you want a performance boost, or just want to undervolt at lower core clocks.

I would also like to know this. I'd love to try modifying the vbios to increase the voltage and overclocking potential.

Way to go! It's great to see the success .

- - - Updated - - - I tried using nvflash, and it gave me an error saying it couldn't find the EEPROM :/. I was trying to extract the vBios for the single 650m card (using "nvflash --save original.bin" command), after having flashed the modded 202 BIOS.

The y500 doesn't have a hidden partition with the OS on it? I know Asus and Dell usually do that. I was under the impression that the visible 25gb one was just a backup of settings and such.

I'm not sure why the laptop works this way, but the gpu clocks drop significantly on battery mode, and unfortunately I don't know how to keep that from happening. It even does this when you are forcing overclocks on the gpu :/. What's worse is if you use the battery preserving feature (to keep the battery at 60% charge), if it's not charging it may enter the lower clock state too.

I don't think the new drivers make much of a difference, so as of now the old drivers are just fine, and more functional for overclockers .

Svl7, do you think you could produce a BIOS mod that increases the maximum gpu voltage, to allow for increased overclocking?

Will this BIOS mod allow you to change the voltage on the gpu and cpu?