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Old Jan 7, 2013, 09:56 PM   #26
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Originally Posted by swarleystinson View Post
Are you sure?. It says there that the Samsung uses gddr3 according to the link to on anandtech's site. Also, I wouldn't call some of those differences small. Plus he's saying he's seeing a huge performance hit.

And, as I just posted, apple's own website claims he should have double the bus width.
Yes, It has 8 GB of DDR3 RAM running at 1600 MHz. That page says nothing about the vram though.

Most of the time the two are within 20% of each other. The samsung wins at skyrim fairly well at enthusiast settings, but the gddr3 clevo creams the gddr5 samsung at civ 5. Considering the two are using different drivers I would say that the two are roughly identical (the clevo gets a higher 3d mark 11 score).

Also remember that the 640m is clocked lower and so will need less memory bandwidth than the 650m.

I doubt that you will see an increase in fps by 3.5 times (100 fps vs 350 fps) by doubling the the memory bendwidth, especially since the 640m can't use all the bandwidth. The 650 ti (almost twice a powerful as the 650m) has a 128 bit bus operating at 1350 mhz. More likely the op is using the intel graphics.

I have a 660m (overclocked to 1058 Mhz compared to about 600-700 for the 640m) and I have never seen the memory controller load go over 60% or about 48 GB/sec. 32 GB/sec should not really have much of an effect on the 640m.
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Old Jan 8, 2013, 01:10 AM   #27
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well said.
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Old Jul 15, 2014, 02:32 PM   #28
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how did you open cuda screen on mac os x ?
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Old Jul 15, 2014, 09:17 PM   #29
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Originally Posted by denizbas View Post
how did you open cuda screen on mac os x ?
Download and install the OS X CUDA drivers from NVIDIA's site. Then open the CUDA preference pane in System Preferences.
2 13" late-2013 rMBPs (base+maxed), maxed late-2013 rMBP 15", maxed early-2011 15", 2010 17", 2 maxed Haswell iMacs (21.5" and 27"), maxed 2012 mini, 2 12-core nMPs, maxed 2013 13" MBA
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Old Jul 16, 2014, 10:54 PM   #30
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The iMac GT 640M is not good
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Old Jul 17, 2014, 04:11 AM   #31
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i got the gtx660m car in my iMac, will installing the cuba software will update my drivers by any chance? whats the benefit having cuba installed?

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