Compare any two graphics cards:
GeForce GT 640 DDR3 vs GeForce GTX 650
IntroThe GeForce GT 640 DDR3 features core speeds of 900 MHz on the GPU, and 1782 MHz on the 2048 MB of DDR3 RAM. It features 384 SPUs along with 32 TAUs and 16 Rasterization Operator Units.Compare those specs to the GeForce GTX 650, which features a GPU core clock speed of 1058 MHz, and 1024 MB of GDDR5 RAM running at 1250 MHz through a 128-bit bus. It also is made up of 384 SPUs, 32 TAUs, and 16 Raster Operation Units.
Display Graphs
BenchmarksThese 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
Power Usage and Theoretical BenchmarksPower Consumption (Max TDP)
Memory BandwidthIn theory, the GeForce GTX 650 will be 40% faster than the GeForce GT 640 DDR3 in general, due to its greater bandwidth. (explain)
Texel RateThe GeForce GTX 650 is a little bit (approximately 18%) more effective at anisotropic filtering than the GeForce GT 640 DDR3. (explain)
Pixel RateIf running with a high resolution is important to you, then the GeForce GTX 650 is the winner, though not by far. (explain)
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
Display Prices
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
Display Specifications
Memory Bandwidth: Memory bandwidth is the largest amount of information (counted in MB per second) that can be transferred past the external memory interface in a second. It is worked out by multiplying the bus width by its memory speed. In the case of DDR memory, the result should be multiplied by 2 again. If DDR5, multiply by ANOTHER 2x. The better the memory bandwidth, the faster the card will be in general. It especially helps with anti-aliasing, HDR and higher screen resolutions. Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that can be processed per second. This is calculated by multiplying the total texture units of the card by the core speed of the chip. The better the texel rate, the better the card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied in one second. Pixel Rate: Pixel rate is the maximum number of pixels that the graphics chip could possibly record to the local memory in a second - measured in millions of pixels per second. The number is worked out by multiplying the number of colour ROPs by the the card's clock speed. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel output rate also depends on quite a few other factors, most notably the memory bandwidth of the card - the lower the bandwidth is, the lower the ability to get to the maximum fill rate.
Display Prices
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.
|
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.