Power target for overclocking

[Carfax83]

Using EVGA Precision X version 4.2, the maximum power target for my GTX 770s is 102%.

But I've seen many reviews of GTX 770s where in the reviewer could set a much higher power target, 109% in the HardOCP review.

So I'm guessing the manufacturer limits the power target for their cards via the BIOS, and it can differ from card to card? And is it really any different from using the overvoltage feature?

Coming from two 580s, I find overclocking on Kepler based GPUs to be strange to put it mildly. Anyway, I'm still getting good results. Both my 770s can hit a sustained boost clock of 1280 MHz. One of them can do 1306, and I suspect the other is being crippled by the close proximity of my sound card to the intake which limits the amount of air it's getting as it's routinely 5 or 6 degrees Celsius above the other one.....which also has my PhysX card right in front of it though not as close.

 

[blackened23]

So I'm guessing the manufacturer limits the power target for their cards via the BIOS, and it can differ from card to card? And is it really any different from using the overvoltage feature?

Correct, the manufacturer sets the limit based on the efficiency of the cooler (or for perhaps other reasons, they basically determine the acceptable limit of TDP) , and it can differ from card to card. It is different from using overvoltage, because 102% of available TDP will be the limit, and you will hit it that much sooner at 102% as compared to a different card that has, for example, 109%. Any type of over-voltage will have you hitting the temperature limit or TDP limit much sooner...

Not sure about the 770, but with the 780 102-103% is the norm for reference, i'm using the EVGA SC ACX which goes up to 106%. It isn't a huge difference in terms of available TDP, but it is a difference based on what the manufacturer feels is an acceptable limit. You can also change whether your card uses temperature limit or TDP limit as a preferred method for overclocking, by default they are linked - but you can unlink them and choose a preference. If you have a good cooler you can use a really high temperature limit and choose that as your preferred. (as opposed to power limit)

 

[Carfax83]

Correct, the manufacturer sets the limit based on the efficiency of the cooler (or for perhaps other reasons, they basically determine the acceptable limit of TDP) , and it can differ from card to card. It is different from using overvoltage, because 102% of available TDP will be the limit, and you will hit it that much sooner at 102% as compared to a different card that has, for example, 109%. Any type of over-voltage will have you hitting the temperature limit or TDP limit much sooner...

Not sure about the 770, but with the 780 102-103% is the norm for reference, i'm using the EVGA SC ACX which goes up to 106%. It isn't a huge difference in terms of available TDP, but it is a difference based on what the manufacturer feels is an acceptable limit. You can also change whether your card uses temperature limit or TDP limit as a preferred method for overclocking, by default they are linked - but you can unlink them and choose a preference. If you have a good cooler you can use a really high temperature limit and choose that as your preferred. (as opposed to power limit)

That's a good explanation, thanks :thumbsup: I haven't tried the prioritization feature (which I think is on power target by default), so I'll try prioritizing temps instead and see if I can gain some more clock speed.

 

[amenx]

Thats odd. My MSI TF 770 has a power target of 111%. I thought they were all like that.

 

[Carfax83]

Thats odd. My MSI TF 770 has a power target of 111%. I thought they were all like that.

Have you overclocked yours yet?

 

[blackened23]

Also, if you're feeling adventurous you can flash your BIOS to accept a higher power limit - a lot of people have done this, but i'm not aware of one specific to the gigabyte 770. I'm sure there's something out there. Also, a higher power limit doesn't necessarily correlate to a guaranteed higher overclock, although it definitely is a good probability. I've heard of some 780s with higher power % than my own SC ACX 780, yet they don't OC quite as well for whatever reason...

With that said, i'm not sure i'd want to flash the BIOS - I had that option with my 780 and chose not to, as the performance I get with the stock BIOS is pretty darn amazing. I get 1202mhz stable when I use +37mV, and i'm perfectly happy with that. Reading of experiences with custom vBIOS, the common theme is that they cause higher idle and load temps which to me lowers the appeal somewhat, as i'm already getting great performance. I guess if I were a hardcore benchmarking type of guy I would do it, but I don't think the difference is all too worthwhile for games. I'd probably get like .5 more fps, ya know which wouldn't be worth it if my temps are 10C higher. Also on an unrelated note, I really enjoy the SC ACX 780 card. I actually don't get past 65C in most games, and the card is pretty whisper quiet even with high manual fan settings...

 

[amenx]

Have you overclocked yours yet?

Yep. Around 1220mhz and 1326 boost. Mem around 7400mhz only.

 

[blackened23]

Are you using the MSI Gamer 770?

You know, i've been looking at reviews of the Gamer series of video cards and the cooler looks like a winner. Have you been pretty satisfied with the noise levels and what-not? I was curious about the gamer series, but of course the 780 gamer SKU isn't released yet. So it was not an option when I was on the market for a GTX 780. So i'm just curious as to how happy you've been with the card in terms of noise levels, etc?

 

[toyota]

I can raise mine to 114% but it does not really matter. even when oced the most it will use is about 101 to 102 and that's in Heaven. for games its less of course.

 

[amenx]

Are you using the MSI Gamer 770?

You know, i've been looking at reviews of the Gamer series of video cards and the cooler looks like a winner. Have you been pretty satisfied with the noise levels and what-not? I was curious about the gamer series, but of course the 780 gamer SKU isn't released yet. So it was not an option when I was on the market for a GTX 780. So i'm just curious as to how happy you've been with the card in terms of noise levels, etc?

Theres only one MSI TF 770 and its the Gamer Ed. The 780 Gamer was just reviewed on Guru3d yesterday, so its definitely out. Quiet card, but the default fan speeds dont seem to go above 44%. Temps around 79-80c when stressed, which leads me to think design priority was for lower noise over temp control. Default temp target 79c in Nvidia Inspector. Quite happy with it, esp with Crysis 3, as I was able to raise the settings a bit more than my 660ti.

 

[blackened23]

Theres only one MSI TF 770 and its the Gamer Ed. The 780 Gamer was just reviewed on Guru3d yesterday, so its definitely out. Quiet card, but the default fan speeds dont seem to go above 44%. Temps around 79-80c when stressed, which leads me to think design priority was for lower noise over temp control. Default temp target 79c in Nvidia Inspector. Quite happy with it, esp with Crysis 3, as I was able to raise the settings a bit more than my 660ti.

Well, I wasn't sure if you were referring to the 770 Lightning or the 770 Gamer. They both use different variants of the Twin Frozr design. In any case, thanks for the information - I just browsed the 780 gamer review and it looks like a great card. And costs the same as the reference while being better as well.

 

[amenx]

Well, I wasn't sure if you were referring to the 770 Lightning or the 770 Gamer. They both use different variants of the Twin Frozr design.

Ah yes, you're right, the Lighting is also TF. What I meant was there is no 'standard' TF, its either the Gamer or Lightning.

 

[Deders]

I found that even though mine has a decent cooler, the gpu itself would crash if too much power was going through it, more than 133% @1.872v

 

[Carfax83]

Yep. Around 1220mhz and 1326 boost. Mem around 7400mhz only.

Thats good.. Is yours the 2GB or 4GB version? My cards must be freaks, because I can overclock them to 7.8 GHZ, despite them being 4GB.. I haven't tried 8 GHZ yet, but I will just to see if they can do it.

 

[Deders]

Be careful when overclocking memory, It has a tendency to degrade if it's too high. I thought I could set mine to 7500 without artifacts but a couple of games proved me wrong.

The Metro last light Benchmark is a good one to get show up artifacts, better than most programs that are designed to do it, Crysis 3 also had a memory related issue:

Just as I came out into the open after the lift drops in the Hydro Dam level, I cloaked and aimed a grenade towards the 1st 5 enemies that congregate as you emerge from the cage, and found that the aiming line wasn't the only line on the screen. So after knocking my memory clock down a couple of notches again this artifact disappeared and I can carry on playing safer in the knowledge that I'm not doing any (or at least as much) damage to the Vram.

 

[blackened23]

Thats good.. Is yours the 2GB or 4GB version? My cards must be freaks, because I can overclock them to 7.8 GHZ, despite them being 4GB.. I haven't tried 8 GHZ yet, but I will just to see if they can do it.

Now that I think of it, that's probably why your cards are capped at 102% - Higher VRAM configurations tap into any available TDP (since higher VRAM cards will always use more power), so that kinda makes sense.

I've heard of other 4GB cards being similar, and I do know the Titan also has a more strict TDP / power limit due to the VRAM - as such the Titan tends to hit the TDP wall a bit sooner than the 3GB GTX 780 as a result.

 

[blackened23]

Be careful when overclocking memory, It has a tendency to degrade if it's too high. I thought I could set mine to 7500 without artifacts but a couple of games proved me wrong.

Well, the 770 does use higher quality VRAM chips and it actually isn't all too uncommon to hit near 8000 with some 770 models...However, only a few select 680 models were able to hit 7000mhz+ with ease. I know most 680 lightnings are able to, probably the DC2 as well. The reference 680 is lucky to even hit 6400-6500...Anyway, If there are issues with the VRAM overclock it usually presents itself as a TDR or artifacts, so it's usually an easy fix.

 

[Carfax83]

Be careful when overclocking memory, It has a tendency to degrade if it's too high. I thought I could set mine to 7500 without artifacts but a couple of games proved me wrong.

I definitely won't use those clocks for 24/7 usage, or even regular gaming. I just want to see if they'll do it

 

[Carfax83]

Now that I think of it, that's probably why your cards are capped at 102% - Higher VRAM configurations tap into any available TDP (since higher VRAM cards will always use more power), so that kinda makes sense.

Yeah, I think you're right. I noticed when overclocking the memory, that my boost clock wasn't as high as with the memory at a lower clock, which implies less TDP was available.

 

[Carfax83]

Managed to bump clock speed up to the next level, 1293 after lowering my memory clocks a bit. However, after about 15 minutes, one of the cards crashed the game, the one with the soundcard right in front of it.

If a card abruptly crashes the game without there being any artifacts or anything, do you think that's indicative of not enough voltage? Too high a temp or it just can't hit that high of a clock speed?

The card that crashed is the same card that runs 7 or 8 degrees warmer than the other due to the soundcard being in front of it btw.

 

[billbobaggins87]

I've been looking into picking up the msi760 gamer card. Fort the price point and the build it looks to be a solid pick after looking at the results of the 780/770 builds.

 

[blackened23]

The card that crashed is the same card that runs 7 or 8 degrees warmer than the other due to the soundcard being in front of it btw.

Yeah, I do think that SLI will lower your overall total overclock. I've noticed that with my prior 680 sli (MSI lightnings) - I could get insanely high overclocks with only a single card in the system, but I had to dial things down a lot in SLI especially when using over-volting (which the lightnings supported). As well, as you noticed - one of the cards do get appreciably warmer in SLi, and that card will likely cause instability at super high clockspeeds.

In any case I wouldn't worry about it too much. If you're anywhere near 1300mhz your performance is insanely good. you can probably get higher - but in SLI those super high overclocks usually require water cooling, since the bottom card (usually) causes the top card to get a bit warmer. Which lowers the overall OC potential.

 

[24601]

Yeah, I do think that SLI will lower your overall total overclock. I've noticed that with my prior 680 sli (MSI lightnings) - I could get insanely high overclocks with only a single card in the system, but I had to dial things down a lot in SLI especially when using over-volting (which the lightnings supported). As well, as you noticed - one of the cards do get appreciably warmer in SLi, and that card will likely cause instability at super high clockspeeds.

In any case I wouldn't worry about it too much. If you're anywhere near 1300mhz your performance is insanely good. you can probably get higher - but in SLI those super high overclocks usually require water cooling, since the bottom card (usually) causes the top card to get a bit warmer. Which lowers the overall OC potential.

Best way to fix this is probably just to get a 7 slot long SLI bridge and get an E-ATX motherboard with PCIe 16x slots in slot 1 and slot 7.

If I was doing only 2x Crossfire (and could find a 7 slot long Crossfire bridge), I would do that with my board.

 

[blackened23]

Best way to fix this is probably just to get a 7 slot long SLI bridge and get an E-ATX motherboard with PCIe 16x slots in slot 1 and slot 7.

If I was doing only 2x Crossfire (and could find a 7 slot long Crossfire bridge), I would do that with my board.

I guess you could do this but many motherboards don't allow it. I do know that with the P8Z77 deluxe (i'm using this) and the Z87 pro, that you have to use 2 specific slots for SLI to maintain dual x8. Fortunately, there is a big gap between the allowable PCIE slots which makes SLI work pretty well for the most part.

Anyway, that is an option if you have a motherboard with perhaps a PLX chip and multiple PCIE x16 lanes. I haven't looked at ASRock motherboards too much but they may be more flexible in that respect - does yours allow that fairly easily?

 

[24601]

I guess you could do this but many motherboards don't allow it. I do know that with the P8Z77 deluxe (i'm using this) and the Z87 pro, that you have to use 2 specific slots for SLI to maintain dual x8. Fortunately, there is a big gap between the allowable PCIE slots which makes SLI work pretty well for the most part.

Anyway, that is an option if you have a motherboard with perhaps a PLX chip and multiple PCIE x16 lanes. I haven't looked at ASRock motherboards too much but they may be more flexible in that respect - does yours allow that fairly easily?

Mine has a PCIe 3.0 PLX chip that supports 16x/16x or 8x/8x/8x/8x (and all the other possible combinations)

This is definitely the easiest way to make sure your cards don't throttle in a good air cooling case for those who don't want to bother (or can't use) water cooling.

This also allows you to use triple slot coolers to full effect.