- Sep 28, 2001
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Today I did a lot of researching and came across several threads where people complained how their cards (in this case GTX 970, but likely applies to other cards as well) are hitting the power limit eg. throttling down or up....and therefore their game experiences would suffer, how the throttling would cause stutters, tearing etc.
* It is hard to believe that NV would have implemented GPU boost (which increases/decreases boost-bins depending on metrics like TDP, power target, temps etc.) if this mechanism itself would cause such problems.
* All those forum posts about those "problems" caused by hitting the power limit (and thus throttling) seemed subjective to me, so I thought there is one metric which would prove/disprove this: FRAME TIME.
If there is problems from hitting the power limit, then frametime would sure show something is up.
So I did testing with Unigine Heaven and with my card (EVGA GTX 970) found a spot where it was getting to the power limit and switching boost-bins FREQUENTLY.
I set MSI Afterburner to the fastest speed to read data, 100ms, and recorded frametime and the curve which shows how the power limit fluctuates at this scene like crazy:
Even with the power limit hit constantly, you can see the frametime being constant. There are no spikes or "lag" or delays introduced by hitting or leaving the power limit.
Therefore I claim here that ANY forum post where people complain about stutters due their cards often hitting the P/L are nothing but nonsense.
It shall also be noted that a boost-bin is (only) 13mhz, so when the card clocks down (or up) 13mhz along with a notch down in voltage, or even two bins...you won't see anything of it in a game or benchmark.
TLDR: Even if your card hits the power limit, even if it hits it very often and GPU boost makes it clock up & down like crazy, this doesn't affect performance or cause stutters or tearing. Prove me wrong!
* Add:
My suspicion: People who play some games or run benchies encounter scenes of various complexity, some which stress the card more, some less. Like a game that is rarely static, one scene might give you 300 FPS - while looking at a super-high-res texture in the other direction is more demanding. AS A RESULT...your card might throttle from one moment to the other. This would be normal. (Many cards are incredibly borderline in regards to their clocks and their power limits). So if you have stutters in such a situation it's not CAUSED by GPU Boost and the fact your card throttles a notch down, but rather by whatever goes on in your game such as the complexity of a scene or a scene-change etc.
This also means that increasing your power limit (as some claim) would hardly help if you have performance problems or stutters due to whatever else. It's a myth that you need at all cost to "keep your card at a constant clock rate" otherwise it would cause problems. We're talking one, two, maybe three boost bins here, 39mhz sure won't matter....and as I showed above, hitting or leaving the power limit has no effect either.
* It is hard to believe that NV would have implemented GPU boost (which increases/decreases boost-bins depending on metrics like TDP, power target, temps etc.) if this mechanism itself would cause such problems.
* All those forum posts about those "problems" caused by hitting the power limit (and thus throttling) seemed subjective to me, so I thought there is one metric which would prove/disprove this: FRAME TIME.
If there is problems from hitting the power limit, then frametime would sure show something is up.
So I did testing with Unigine Heaven and with my card (EVGA GTX 970) found a spot where it was getting to the power limit and switching boost-bins FREQUENTLY.
I set MSI Afterburner to the fastest speed to read data, 100ms, and recorded frametime and the curve which shows how the power limit fluctuates at this scene like crazy:
Even with the power limit hit constantly, you can see the frametime being constant. There are no spikes or "lag" or delays introduced by hitting or leaving the power limit.
Therefore I claim here that ANY forum post where people complain about stutters due their cards often hitting the P/L are nothing but nonsense.
It shall also be noted that a boost-bin is (only) 13mhz, so when the card clocks down (or up) 13mhz along with a notch down in voltage, or even two bins...you won't see anything of it in a game or benchmark.
TLDR: Even if your card hits the power limit, even if it hits it very often and GPU boost makes it clock up & down like crazy, this doesn't affect performance or cause stutters or tearing. Prove me wrong!
* Add:
My suspicion: People who play some games or run benchies encounter scenes of various complexity, some which stress the card more, some less. Like a game that is rarely static, one scene might give you 300 FPS - while looking at a super-high-res texture in the other direction is more demanding. AS A RESULT...your card might throttle from one moment to the other. This would be normal. (Many cards are incredibly borderline in regards to their clocks and their power limits). So if you have stutters in such a situation it's not CAUSED by GPU Boost and the fact your card throttles a notch down, but rather by whatever goes on in your game such as the complexity of a scene or a scene-change etc.
This also means that increasing your power limit (as some claim) would hardly help if you have performance problems or stutters due to whatever else. It's a myth that you need at all cost to "keep your card at a constant clock rate" otherwise it would cause problems. We're talking one, two, maybe three boost bins here, 39mhz sure won't matter....and as I showed above, hitting or leaving the power limit has no effect either.
Last edited:
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