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GeForce GT 640 DDR3 vs GeForce GTX 650
Intro
The GeForce GT 640 DDR3 features a GPU core speed of 900 MHz, and the 2048 MB of DDR3 RAM is set to run at 1782 MHz through a 128-bit bus. It also is made up of 384 Stream Processors, 32 Texture Address Units, and 16 Raster Operation Units.Compare those specifications to the GeForce GTX 650, which has GPU clock speed of 1058 MHz, and 1024 MB of GDDR5 RAM set to run at 1250 MHz through a 128-bit bus. It also features 384 Stream Processors, 32 TAUs, and 16 Raster Operation Units.
Benchmarks
These are real-world performance benchmarks that were submitted by Hardware Compare users. The scores seen here are the average of all benchmarks submitted for each respective test and hardware.
3DMark Fire Strike Graphics Score
| GeForce GTX 650 |
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2263 points |
| GeForce GT 640 DDR3 |
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1560 points |
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Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
| GeForce GTX 650 |
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64 Watts |
| GeForce GT 640 DDR3 |
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65 Watts |
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Memory Bandwidth
In theory, the GeForce GTX 650 should perform much faster than the GeForce GT 640 DDR3 in general. (explain)
| GeForce GTX 650 |
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80000 MB/sec |
| GeForce GT 640 DDR3 |
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57024 MB/sec |
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Texel Rate
The GeForce GTX 650 is a small bit (approximately 18%) better at texture filtering than the GeForce GT 640 DDR3. (explain)| GeForce GTX 650 |
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33856 Mtexels/sec |
| GeForce GT 640 DDR3 |
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28800 Mtexels/sec |
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Pixel Rate
If using lots of anti-aliasing is important to you, then the GeForce GTX 650 is a better choice, but it probably won't make a huge difference. (explain)| GeForce GTX 650 |
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16928 Mpixels/sec |
| GeForce GT 640 DDR3 |
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14400 Mpixels/sec |
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Please note that the above 'benchmarks' are all just theoretical - the results were calculated based on the card's specifications, and real-world performance may (and probably will) vary at least a bit.
Price Comparison
GeForce GT 640 DDR3Amazon.com
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GeForce GTX 650Amazon.com
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Please note that the price comparisons are based on search keywords - sometimes it might show cards with very similar names that are not exactly the same as the one chosen in the comparison. We do try to filter out the wrong results as best we can, though.
Specifications
| Model | GeForce GT 640 DDR3 | GeForce GTX 650 |
|---|---|---|
| Manufacturer | nVidia | nVidia |
| Year | June 2012 | September 2012 |
| Code Name | GK107 | GK107 |
| Memory | 2048 MB | 1024 MB |
| Core Speed | 900 MHz | 1058 MHz |
| Memory Speed | 3564 MHz | 5000 MHz |
| Power (Max TDP) | 65 watts | 64 watts |
| Bandwidth | 57024 MB/sec | 80000 MB/sec |
| Texel Rate | 28800 Mtexels/sec | 33856 Mtexels/sec |
| Pixel Rate | 14400 Mpixels/sec | 16928 Mpixels/sec |
| Unified Shaders | 384 | 384 |
| Texture Mapping Units | 32 | 32 |
| Render Output Units | 16 | 16 |
| Bus Type | DDR3 | GDDR5 |
| Bus Width | 128-bit | 128-bit |
| Fab Process | 28 nm | 28 nm |
| Transistors | 1300 million | 1300 million |
| Bus | PCIe 3.0 x16 | PCIe 3.0 x16 |
| DirectX Version | DirectX 11.0 | DirectX 11.0 |
| OpenGL Version | OpenGL 4.2 | OpenGL 4.3 |
Memory Bandwidth: Bandwidth is the max amount of information (measured in megabytes per second) that can be transported past the external memory interface in one second. It's worked out by multiplying the interface width by its memory clock speed. In the case of DDR type memory, the result should be multiplied by 2 once again. If DDR5, multiply by ANOTHER 2x. The better the bandwidth is, the better the card will be in general. It especially helps with AA, HDR and higher screen resolutions.
Texel Rate: Texel rate is the maximum texture map elements (texels) that are processed per second. This figure is calculated by multiplying the total amount of texture units of the card by the core clock speed of the chip. The higher this number, the better the card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed in one second.
Pixel Rate: Pixel rate is the maximum number of pixels the video card could possibly write to its local memory in one second - measured in millions of pixels per second. The figure is calculated by multiplying the amount of colour ROPs by the the card's clock speed. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel rate is also dependant on quite a few other factors, especially the memory bandwidth of the card - the lower the memory bandwidth is, the lower the potential to reach the maximum fill rate.
GeForce GT 640 DDR3Amazon.com
Check prices at:
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GeForce GTX 650Amazon.com
Check prices at:
|
Please note that the price comparisons are based on search keywords - sometimes it might show cards with very similar names that are not exactly the same as the one chosen in the comparison. We do try to filter out the wrong results as best we can, though.
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Comments
3 Responses to “GeForce GT 640 DDR3 vs GeForce GTX 650”woow... look @ the TDP
Certainly going for the GTX 650 is a better choice if you are choosing between these two cards. Why to chhoose:
The higher bandwidth & GDDR5 bus (over the outdated DDR3 bus)
And even the Power consuption is lower in the GTX 650 with much better performance.
I have both cards.
I have both , the MSI GTX650 with 1gb ddr5 and an OEM HP GT640 with 4gb ddr3 . Passmark scores for the GTX650 is only 30 or so points higher then the GT640. BUT, I can use MSI's Afterburner to push the score to about 200 points higher then the stock out of the box settings. So overclocking the GTX yields greater results, but the stock settings are very similar between the two cards.
HOWEVER ! Both needed MORE power to achieve full performance. They both worked with the factory Dell 760 305w PSU, but both achieved much higher Passmark scores when a higher output PSU (Thermaltake 700w) was installed. Approx. 600 + - points higher, which is a HUGE improvement. This is not due to Dell limiting the PCI-E slots power, as the GT640 does not use a PCI-E power cable, as does the GTX650. The GT640 gets all of it's power through the PCI-E slot. So if you think you can run a GT640 with a lower powered PSU, you might miss out on a major part of the cards abilities. SO don't let the low TDP fool you, you still need a decent PSU to properly power these two cards to achieve their full potential. What the low TDP does allow, is the ability to use the cards with a smaller PSU to start off, which will let you determine if you are able to run the card fully with your current PSU. Don't assume you're getting all of it's capabilities, you'll need to run some benchmark tests and compare your cards score vs other average scores. If you are WAY off, you'll probably benefit with a PSU upgrade. This way, you can see if the PSU you have will get the job done before spending the coin on a larger PSU. To give an example, I still have the DEll supplied HD3450, which achieves approx. the same Passmark score as the GT640 when using the stock Dell PSU. The GT640 smokes the HD3450 when the larger PSU is installed.