Overclocking: When Headroom Exceeds Clockspeed Limits

Last but not least we have our customary look at overclocking performance. With all 3 of our cards being based on the same reference design, we expect to see some relatively consistent results between the cards. At the same time NVIDIA has told us that GTX 750 has some very interesting overclocking properties, and boy they weren’t kidding.

On a quick note, as a GPU Boost 2.0 product, overclocking on the GTX 750 series is not any different than on other GTX 700 series cards. It’s still based on offset overclocking, with the user adjusting offsets for the final overclock. But with that said there are two things to point out. The first is that the power target is limited to 100% on all cards. Because these are sub-75W cards, NVIDIA is not allowing anyone to exceed the card’s default TDP, so you only have as much power to play with as you started with. Second of all, none of our cards had available overvoltage bins. Apparently some cards do, but ours did not, so our voltage bins maxed out at the default bins you see listed.

Finally, all 3 cards have a maximum clock offset of 135MHz. This will be an important fact in a little bit.

GeForce GTX 750 Series Overclocking
  GTX 750 Ti (Ref) Zotac GTX 750 Ti Zotac GTX 750
Shipping Core Clock 1020MHz 1033MHz 1033MHz
Shipping Max Boost Clock 1150MHz 1175MHz 1163MHz
Shipping Memory Clock 5.4GHz 5.4GHz 5.0GHz
Shipping Max Boost Voltage 1.168v 1.137v 1.187v
       
Overclock Core Clock 1155MHz 1168MHz 1168MHz
Overclock Max Boost Clock 1285MHz 1310MHz 1298MHz
Overclock Memory Clock 6.3GHz 6.1GHz 6.0GHz
Overclock Max Boost Voltage 1.168v 1.137v 1.187v

As we can quickly see, two patterns emerge. The first is that with every card equipped with 6GHz memory (though we remain unsure which mode the Zotac GTX 750’s is in), each and every card hits at least 6GHz, and sometimes a bit more. With the 128-bit memory bus generally providing the biggest bottleneck for GM107, the fact that there is 12%+ overclocking headroom here is going to be very helpful in feeding the tiny beast that is GM107.

More significantly however is the core overclock. We maxed out every single one. Every card, from the NVIDIA reference card to the Zotac cards, had no trouble overclocking by the full 135MHz to their respective maximum overclocks. The Zotac GTX 750 Ti, having the highest maximum boost clock by default, is technically the winner here at 1310MHz. But at this point everyone is a winner. Going by the maximum boost clock, every card is capable of an 11% core overclock, to go with that tasty 12% memory overclock.

The fact of the matter is that this is not something we normally encounter. Sub-75W cards are not poor overclockers, but they’re not usually strong overclockers either, which is why a 135MHz offset limit makes sense at first glance. But it’s clear that NVIDIA underestimated their own overclocking potential here when setting the specifications for these cards, as there’s seeming some headroom left untapped. Without additional offset room it’s impossible to say just how much more overclocking headroom remains – it may not be very much – but there should be room for at least some additional overclocking.

At this point with cards already in the pipeline we’ll have to take a look at individual cards and see what manufacturers have set their offset limits at. If they have followed NVIDIA’s specifications, then they’ll be equally limited. But hopefully with the launch now behind them, NVIDIA’s partners can work with NVIDIA on making greater offsets available on newer batches of cards.

Metro: Last Light - 1920x1080 - High Quality

Company of Heroes 2 - 1920x1080 - High Quality + Low AA

Company of Heroes 2 - Min. Frame Rate - 1920x1080 - High Quality + Low AA

Bioshock Infinite - 1920x1080 - Ultra Quality + DDoF

Battlefield 4 - 1920x1080 - High Quality

Crysis 3 - 1920x1080 - Medium Quality + FXAA

Depending on the game being used, the benefits from overclocking range from 9% to 12%, roughly in-line with our overclocks. For the GTX 750 this is sometimes enough to catch the stock clocked R7 260X, but even with this overclock the GTX 750 Ti will still generally trail the R7 265.

Load Power Consumption - Crysis 3

Load Power Consumption - FurMark

Load GPU Temperature - Crysis 3

Load GPU Temperature - FurMark

Load Noise Levels - Crysis 3

Load Noise Levels - FurMark

On the other hand, because of the hard TDP limit of 100%, this extra performance is relatively cheap. Video card power consumption moves by only a few watts, and then a few watts of CPU time on top of that. For all practical purposes overclocking can extend NVIDIA’s already incredible performance-per-watt ratio by another 10% with no meaningful impact on noise. Given the consistency of overclocking headroom we’ve seen in our GTX 750 series samples, this is one of those scenarios where overclocking is going to be a reasonable and (relatively) fool proof action to take.

Power, Temperature, & Noise Final Words
Comments Locked

177 Comments

View All Comments

  • EdgeOfDetroit - Tuesday, February 18, 2014 - link

    This card (Evga 750 Ti OC) is replacing a 560Ti for me. Its slower but its not my primary game machine anymore anyways. I'll admit I was kinda bummed when the 700 series stopped at the 760, and now that the 750 is here, its like they skipped the true successor to the 560 and 660. I can probably still get something for my 560Ti, at least.
  • rhx123 - Tuesday, February 18, 2014 - link

    I wonder if we'll get the 750Ti or even the 750 in a half height config.

    It would be nice for HTPCs given the power draw, but I'm not optimistic.
    There's still nothing really decent in the half height Nvidia camp.
  • Frenetic Pony - Tuesday, February 18, 2014 - link

    "it is unfortunate, as NVIDIA carries enough market share that their support (or lack thereof) for a feature is often the deciding factor whether it’s used"

    No this time. Both the Xbone and PS4 are fully feature compliant, as is GCN 1.1 cards, heck even GCN 1.0 has a lot of the features required. With the new consoles, especially the PS4, selling incredibly well these are going to be the baseline, and if you buy a NVIDIA card without it, you be SOL for the highest end stuff.

    Just another disappointment with Maxwell, when AMD is already beating Nvidia price for performance wise very solidly. Which is a shame, I love their steady and predictable driver support and well designed cooling set ups. But if they're not going to compete, especially with the rumors of how much Broadwell supposedly massively improves on Intel's mobile stuff, well then I just don't know what to say.
  • Rebel1080 - Tuesday, February 18, 2014 - link

    Can we all come to a consensus by declaring the 8th console generation an a epic bust!!! When the Seventh console generation consoles (PS3/XB360) made their debut it took Nvidia and AMD 12-18 months to ship a mainstream GPU that could match or exceed thier performance. This generation it only took 3 months at 2/3rds the price those cards sold at (3870/8800GT).

    It's pretty condemning that both Sony and MSFT's toy boxes are getting spanked by $119-149 cards. Worst of all the cards are now coming from both gpu companies for which I'm sure gives Nvidia all smiles.
  • FearfulSPARTAN - Tuesday, February 18, 2014 - link

    Really an epic bust.... Come on now we all knew from the start they were not going to be bleeding edge based on the specs. They were not going for strong single threaded performance they were aiming for well threaded good enough cpu performance and the gpus they had were average at their current time. However considering the ps4 and x1 are selling very well calling the entire gen a bust already is just stupid. You dont need high performance for consoles when you have developers coding to scrape every bit of performance they can out of your hardware, thats something we dont have in the pc space and why most gamers are not using those cards that just met last gen console performance seven years ago.
  • Rebel1080 - Tuesday, February 18, 2014 - link

    They're selling well for the same reasons iTards keep purchasing Apple products even though they only offer incremental updates on both hardware and less on software. It's something I like to call "The Lemming Effect".

    Developers code to the metal but that only does so much and then you end up having to compromise the final product via lower res, lower fps, lower texture detail. Ironcially I was watching several YouTube videos of current gen games (BF3&4, Crysis 3, Grid 2, AC4) running at playable fps between 720p & 900P on a Radeon 3870.
  • oleguy682 - Tuesday, February 18, 2014 - link

    Except that unlike Apple, Sony and Microsoft are selling each unit at a loss once the BOM, assembly, shipping, and R&D are taken into consideration. The PS3 was a $3 billion loss in the first two years it was available. The hope is that licensing fees, add-ons, content delivery, etc. will result in enough revenue to offset the investment, subsidize further R&D, and leave a bit left over for profit. Apple, on the other hand, is making money on both the hardware and the services.

    And believe it or not, there are a lot more console gamers than PC gamers. Gartner estimates that in 2012, PC gaming made up only $14 billion of the $79 billion gaming market. This does include hardware, in which the consoles and handheld devices (likely) get an advantage, but 2012 was before the PS4 and Xbone were released.

    So while it might be off-the-shelf for this generation, it was never advertised as anything more than a substantial upgrade over the previous consoles, both of which were developed in the early 2000s. In fact, they were designed for 1080p gaming, and that's what they can accomplish (well, maybe not the Xbone if recent reports are correct). Given that 2160p TVs (because calling it 4K is dumb and misleading) are but a pipe dream for all but the most well-heeled of the world and that PCs can't even come close to the performance needed to drive such dense displays (short of spending $1,000+ on GPUs alone), there is no need to over-engineer the consoles to do something that won't be asked of them until they are near EOL.
  • Rebel1080 - Tuesday, February 18, 2014 - link

    PC Gaming is growing faster globally than the console market because purchasing consoles in many nations is extremely cost prohibitive due to crushing tariffs. Figure that in 3yrs time both Intel and AMD will have IGPs that will trounce the PS4 and will probably sell for under $99 USD. PC hardware is generally much more accessible to people living in places like Brazil, China and India compared to consoles. It would actually cost less to build a gaming PC if you live there.

    The console market is the USA, Japan and Western Europe, as the economies of these nations continue to decline (all 3 are still in recession) people who want to game without spending a ton will seek lower cost alternatives. With low wattage cards like the 750Ti suddenly every Joe with a 5yr old Dell/HP desktop can now have console level gaming for a fraction of the cost without touching any of his other hardware.
  • Rebel1080 - Tuesday, February 18, 2014 - link

    http://www.gamespot.com/articles/sony-says-brazil-...
  • oleguy682 - Wednesday, February 19, 2014 - link

    Brazil is only Brazil. It does not have any bearing on China or India or any other developing nation as they all choose their own path on how they tax and tariff imports. Second, throwing a 750Ti into a commodity desktop (the $800-1,200 variety) from 3 years ago, let alone 5, is unlikely to result in performance gains that would turn it into a full-bore 1080p machine that can run with the same level of eye-candy as a PS4 or XBone. The CPU and memory systems are going to be huge limiting factors.

    As far as the PC being a faster growing segment, the Gartner report from this fall thinks that PC gaming hardware and software will rise from the 2012 baseline of 18.3% of spending to 19.4% of spending in 2015. So yes, it will grow, but it's such a small share already that it barely does anything to move the needle in terms of where gaming goes. In contrast, consoles are expected to grow from 47.4% to 49.6% of spending. The losing sectors are going to be handheld gaming, eaten mostly by tablets and smartphones. PCs aren't dying, but they aren't thriving, regardless of what Brazil does with PS4 imports in 2014.

Log in

Don't have an account? Sign up now