Overclocking an OEM GT 640 GDDR5

[tabascosauz]

Hey guys,

I have an Dell XPS 8500 with an i7-3770 (non K), 12GB of DDR3-1600.

The graphics card is a 1GB GT 640 GDDR5.
This card is OEM only, based on new GK107 with 80GBps 128-bit GDDR5.
The core clock is 954 MHz, shader clock 1908 MHz and memory 2500 MHz.

It is basically a GTX 650, except that the core clock is lower (954 vs 1058) therefore
the fill rate is lower (30.4 vs 33.9 billion/sec). I do not know the shader clock on the
GTX 650.

The data rates of both 640 and 650 are 5000GBps (they have the same memory).

Question is, now that I have MSI Afterburner and it is working, should I overclock my
GT 640 GDDR5 to match the figures of the 650? I know it doesn't look like a lot, but I've
seen a lot of vids and the GTX 650 is capable of running BF3 (which is my main game) at
medium with FXAA at a decent 60 fps, while my GT 640 works fine at low with 60-80 fps but
struggles at medium, managing only 30-40 fps.

Any ideas guys? I'm really not in a hurry to do this; I can make do with low but those of
you familiar with BF3 might know that low and medium have the biggest difference in terms
of texture and shadow quality.

Heck the two even look the same.
GT640 image: http://www.geforce.com/Active/en_US/shared/images/products/geforce-gt-640-oem/geforce-gt-640-f-1000x580.png
GTX650 image: http://www.geforce.co.uk/Active/en_US/shared/images/products/geforce-gtx-650/geforce-gtx-650-3qtr.png

I did notice just then that the 650 has a bigger fan, but only slightly.

 

[amuffin]

You can try, but it isn't guaranteed that you will get the performance of the GTX650.

There is no shader clock on the Kepler series.

 

[tabascosauz]

Thanks.

Yeah, I read about the unified clockspeeds a while back, but I just wrote 1908 because MSI Afterburner said so. Sorry

I'll try taking it up a bit by bit, then checking with Kombustor to see how the GPU is taking it. Any suggestions for clock speeds would be appreciated.

 

[blazorthon]

I don't see much reason for it to be incapable of the small overclock needed to reach reference GTX 650 performance. It'd have to be an incredibly bad sample to be incapable of a mere what, 18% overclock on the GPU.

 

[animekenji]

GTX650 requires an external power connector to reach the clocks that it has and it has better cooling than the OEM GT640 GDDR5. I am guessing that you don't have much overclocking room with this card without the power connector. You could probably solder on a power connector, add better cooling and flash a GTX650 BIOS, but you'd be better off to just sell the GT640 and put the money towards a genuine GTX650. It's a lot less trouble in the long run and at least you get a warranty with the new card.

 

[tabascosauz]

Well, I was thinking of ditching the GT 640 altogether for a GTX 660.

I'll see. Right now, I am getting better performance across my games.

 

[Fishwithadeagle]

I still think that the gt640 is nowhere near the gtx 650 but that is my opinion. Get the 7870 hawk instead of the 66, better price/performance.

 

[blazorthon]

The GT 640 and the GTX 650 are the exact same card except for a moderate frequency difference and the type of memory and other superficial differences. Even with its power limit from lacking a PCIe connector, it should be fine because the GTX 650 does in fact not pull anywhere near enough power to need the PCIe connector. The GTX 650 Ti pulls considerably more power and it could get away with not using the connector if Nvidia wanted it to (the same is true for the Radeon 7770 and the Radeon 7750s that have the connector).

I do agree with upgrading to a different card altogether, but the 7870 Hawk is a not the best choice. The Sapphire 7870 XT is faster and cheaper or the same price everywhere I see it.

 

[tabascosauz]

Best answer selected by tabascosauz.

 

[tabascosauz]

The GT 640 and the GTX 650 are the exact same card except for a moderate frequency difference and the type of memory and other superficial differences. Even with its power limit from lacking a PCIe connector, it should be fine because the GTX 650 does in fact not pull anywhere near enough power to need the PCIe connector. The GTX 650 Ti pulls considerably more power and it could get away with not using the connector if Nvidia wanted it to (the same is true for the Radeon 7770 and the Radeon 7750s that have the connector).

I do agree with upgrading to a different card altogether, but the 7870 Hawk is a not the best choice. The Sapphire 7870 XT is faster and cheaper or the same price everywhere I see it.

Thank you.

Anyways, I believe that the GT 640 GDDR5 does have a power connector...

When I saw the 7870 XT, I thought that I was seeing things. I mean, it's the only Tahiti LE card with dual fans, and a very good cooling solution too. But when I saw the dimensions, my heart sank. 10.8 inches... no way I'm fitting that into my case.

If I actually upgrade, I think I'll go either XFX DD 7870, Asus DCII 7870, Asus DCII 660 or EVGA Sig2 660.

But just another question: I have Geforce Experience installed becuz I'm lazy to tweak my games individually It automatically provides updates for the driver. I'm sort of unfamiliar with OEM things; will there be problems if I update to the suggested 314.07 driver ( think it's beta)? I have stock 296.33 OEM driver...

 

[blazorthon]

Glad to help

Well, that's easily checked by looking at your card, if you want to.

Sorry to get your hopes up

I'd also consider the Gigabyte 7870 WindForce X3. It has a good factory overclock, the cooler that supposedly has the best cooling performance to low noise ratio, and is often priced low.

With your GT 640 GDDR5, you should be able to update the driver if you want to. You could check Dell's website to see if they have a specific driver that is more up to date than your current one. If not, then you can try the generic Nvidia drivers from Nvidia's website and they're probably work just fine anyway.