Introduction
About one month ago, NVIDIA released their GeForce GT 640 Series without much fanfare. The new GT 640 is based on the company's award-winning Kepler architecture, but uses a smaller, less powerful graphics processor than the GK104 GPU, we've come to love on GTX 670, 680 and 690. GT 640 also does not feature NVIDIA's boost clock algorithm which dynamically adjust clocks to increase performance if the card is running below its TDP limit.
The GeForce GT 640 is based on a 28 nm GK107 GPU, with a CUDA core count of 384. Unlike its high-end brethren, the card uses cheaper, but slower DDR3 memory, which you would also find on your mobo's memory modules, for example.
ZOTAC's GT 640, is one of the few single-slot GTX 640 cards on the market, which means it might be interesting for HTPC users. Clocks have remained at the NVIDIA default of 891 MHz GPU and 900 MHz memory. While there are variants with 1 GB memory, ZOTAC has put 2 GB on the card, whether this makes much sense is something we will know at the end of the review. Price-wise GT 640 is definitely not cheap, with a current retail price of $110 there are many options to consider, cheaper and more expensive.
GeForce GT 640 Market Segment Analysis | GeForce GT 520 | Radeon HD 5550 | GeForce GT 440 | Radeon HD 5670 | GeForce GT 640 | Radeon HD 6670 | GeForce GTS 450 | Radeon HD 5750 | Radeon HD 5770 | Radeon HD 7750 | GeForce GTX 550 Ti | Radeon HD 6790 | Radeon HD 6850 |
---|
Shader Units | 48 | 320 | 96 | 400 | 384 | 480 | 192 | 720 | 800 | 512 | 192 | 800 | 960 |
---|
ROPs | 4 | 8 | 4 | 8 | 16 | 8 | 16 | 16 | 16 | 16 | 24 | 16 | 32 |
---|
Graphics Processor | GF119 | Redwood | GF108 | Redwood | GK107 | Turks | GF106 | Juniper | Juniper | Cape Verde | GF116 | Barts | Barts |
---|
Transistors | ???M | 627M | 585M | 627M | ???M | 716M | 1170M | 1040M | 1040M | 1500M | 1170M | 1700M | 1700M |
---|
Memory Size | 1024 MB | 1024 MB | 1024 MB | 1024 MB | 2048 MB | 1024 MB | 1024 MB | 1024 MB | 1024 MB | 1024 MB | 1024 MB | 1024 MB | 1024 MB |
---|
Memory Bus Width | 64 bit | 128 bit | 128 bit | 128 bit | 128 bit | 128 bit | 128 bit | 128 bit | 128 bit | 128 bit | 192 bit | 256 bit | 256 bit |
---|
Core Clock | 810 MHz | 550 MHz | 823 MHz | 775 MHz | 902 MHz | 800 MHz | 783 MHz | 700 MHz | 850 MHz | 800 MHz | 900 MHz | 840 MHz | 775 MHz |
---|
Memory Clock | 800 MHz | 1000 MHz | 800 MHz | 1000 MHz | 891 MHz | 1000 MHz | 900 MHz | 1150 MHz | 1200 MHz | 1125 MHz | 1026 MHz | 1050 MHz | 1000 MHz |
---|
Price | $45 | $50 | $60 | $70 | $110 | $65 | $105 | $90 | $110 | $110 | $120 | $120 | $140 |
---|