The appearance on the market of video cards of the 7700 line happened in February 2012. Then two models were released 7750 and 7770. These were budget video adapters of the middle segment. The appearance of the entire 7700 line was a logical continuation of the release of the Radeon HD 7xxx series. The top model (at that time HD 7950) came out a month earlier.
During the production of the entire line (February 2012 – August 2013), 4 models of video cards related to the AMD Radeon HD 7700 series were released. All of them were based on the same technical process and had very similar characteristics, although the difference in performance between the fastest and slowest cards in the line was almost threefold.
The explanation was quite simple: the models differed significantly in the number of unified shader processors. Of the entire HD 7xxx series, only the 7700 had this feature.
To some extent, this made the 7700 series universal, since, on the one hand, the buyer could choose the performance he was interested in by purchasing a particular adapter. On the other hand, the presence of as many as 4 models with the same filling made a lot of confusion in the classification of video adapters.
A similar confusion persisted in the next generation of AMD products – the R200 family, and only a couple of years later, with the advent of the R400, the situation with the classification improved markedly.
Therefore, until now, many AMD fans recall with horror the period when, having confused only two digits in the adapter index, it was possible to seriously miscalculate the performance. For example, the performance of the 7970 and 7790 differed by more than three times; and the performances of the 7750 and 7570 were almost the same.
AMD Radeon HD 7700 series specifications
AMD Radeon HD 7700 series cards have the following features:
- chip used – Cape Verde / Bonaire;
- technical process – 28 nm;
- chip frequency – 800/1000 MHz;
- memory frequency – 1125 MHz;
- used memory – GDDR5, 1 or 2 GB;
- data bus width – 128 bits;
- hardware API support – Direct X 11.1, partially 12.0; OpenGl – 4.2; OpenCl – 1.2;
- interface – PCIEx16 v 3.0;
- power consumption – from 47 to 85 watts.
At the time of its appearance, these cards met the most modern requirements for hardware and software compatibility with all existing means for creating computing systems at that time.
Read Graphics Card Features, Characteristics, Types.
Differences Between 7700 Series Models
The main differences within the series were in the configuration of the cores. The “junior” adapters in the series differed from the “senior” ones only in the number of processors per chip.
Attention! On AMD cards, the core configuration is described by three numbers:
- the number of unified shader processors (UWP);
- the number of texture units (TB);
- the number of rasterization blocks (BR).
The main contribution to performance is made by UWB.
So the 7700 series video adapters had the following core configurations:
- Radeon HD 7730: UWB – 384, TB – 24, BR – 8.
- Radeon HD 7750: UWB – 512, TB – 32, BR – 16.
- Radeon HD 7770: UWB – 640, TB – 40, BR – 16.
- Radeon HD 7790: UWB – 896, TB – 56, BR – 16.
There were also minor differences in the series. So the chip frequencies in the 30th and 50th models were artificially lowered to 800 MHz (instead of 1000 MHz in the 70th and 90th models). In addition, 7790-based cards had 33% faster memory (1500 MHz instead of 1125 MHz).
For the rest of the characteristics, the adapters under consideration were absolutely identical.
Graphics Card Specifications
The Radeon HD 7770 was arguably the most popular in the entire 77xx line, as it combined sufficient performance at an affordable price. At the time of release, the price for one shader (UWB) was about $ 0.19 and was the lowest in the entire 77xx series.
Until now, 7770 cards can be found on sale, mainly in the secondary market. However, taking into account the fact that there are also new ones, we can conclude that the model turned out to be quite “tenacious”, despite the age of seven (the date of the map was released on 15.02.2012).
This video card is based on the Capo Verde XT chip containing 1.5 billion transistors. The crystal area is 123 sq. mm. The card uses 1GB GDDR5 memory clocked at 1125 MHz (4500 MHz effective). The width of the data bus is 128 bits.
With these parameters, the memory bandwidth is about 72 GB / s.
The peak fill rate is 16 GPix / s or 40 GTex / s.
The theoretical performance in FP32 is about 1.28 TFlops, which is quite good for a card approaching 7 years old.
The card is fully compatible with the DirectX-11 API and partially compatible with DirectX-12.
For comparison with NVidia, it can be noted that its “analog 7770 in the middle segment”, namely the GTX750 card, which has similar characteristics (512 scalar processors and performance
FP32 at 1.044 TFlops), they were able to do it only in February 2014, that is, two years later than AMD. This means that AMD had no competitors in this price segment for two years.
Attention! When evaluating the performance of cards from AMD and NVidia, keep in mind that AMD universal shader processors are not the same as NVidia scalar processors (the so-called CUDA). On average, UWB performance is 20% less than CUDA.
Read also Best Laptop Graphics Card For Gaming
Radeon HD 7700 Series Graphics Accelerators
Based on the 77xx series, many models from various manufacturers have been released. Accelerators from Gigabyte were the most diverse. They were produced both in the reference configuration and with slightly overclocked chip and memory frequencies.
Separately, it should be noted the products of Asus, which produced almost the entire line with 2 GB memory.
Graphics accelerators from MSI were equipped with quite good software that allowed to automatically select the overclocking parameters of video adapters.
Architectural features
The main feature of the entire 77xx series was that all the models that were included in it were based on the Graphics Core Next or GCN architecture. 77xx cards were among the first to implement GCN version 1.0
AMD currently has its fourth version of GCN. Moreover, unlike NVidia, which has changed its approach to architecture twice over the past 5 years (switching from Maxwell to Pascal, and then again to Maxwell, which was called Turing for beauty), AMD does not change the architecture, but only modifies the existing one.
And if at the same time AMD products remain competitive in comparison with NVidia products, this indicates a very successful architectural solution found back in 2012.
Another important architectural feature of the 77xx series was that its top-end 7790 was one of the first cards to support the Mantle API. Namely, the emergence of Mantle prompted Microsoft to make significant improvements to its DirectX.
Check out How T Overclock AMD Radeon HD 6670?
Overclocking AMD Radeon HD 7700 series
The overclocking characteristics of chips with GCN 1.0 architecture are very good.
Usually, when using air or liquid cooling, it was possible to reach a chip frequency of about 1270 MHz, which corresponded to an overclocking of + 27%.
Memory overclocking was much better. Peak values of the memory frequency were 1630 MHz, which was equivalent to overclocking + 45%. However, it should be noted that such overclocking is quite common for GDDR5.
