|Recommended System Requirements|
|Game||Radeon HD 7970 Crossfire||Radeon HD 7990|
|Watch Dogs 2||13%||19%|
|Need For Speed||8%||15%|
|Forza Horizon 3||17%||9%|
In terms of overall gaming performance, the graphical capabilities of the AMD Radeon HD 7990 are very slightly better than the AMD Radeon HD 7970 Crossfire.
The Radeon HD 7990 has a 25 MHz higher core clock speed and the same number of Texture Mapping Units as the HD 7970. This results in the Radeon HD 7990 providing 6.4 GTexel/s better texturing performance. This still holds weight but shader performance is generally more relevant, particularly since both of these GPUs support at least DirectX 10.
The Radeon HD 7990 has a 25 MHz higher core clock speed than the HD 7970 and the same number of Render Output Units. This results in the Radeon HD 7990 providing 1.6 GPixel/s better pixeling performance. However, both GPUs support DirectX 9 or above, and pixeling performance is only really relevant when comparing older cards.
The Radeon HD 7990 was released over a year more recently than the HD 7970, and so the Radeon HD 7990 is likely to have better driver support, meaning it will be more optimized for running the latest games when compared to the HD 7970.
Both GPUs exhibit very powerful performance, so it probably isn't worth upgrading from one to the other, as both are capable of running even the most demanding games at the highest settings.
The Radeon HD 7970 Crossfire and the Radeon HD 7990 have the same amount of video memory, but are likely to provide slightly different experiences when displaying game textures at high resolutions.
The Radeon HD 7990 has 48 GB/sec greater memory bandwidth than the HD 7970, which means that the memory performance of the Radeon HD 7990 is noticeably better than the HD 7970.
Both the Radeon HD 7970 Crossfire and the Radeon HD 7990 have 4096 Shader Processing Units. While the two GPUs have the same number of SPUs, the actual performance delivered by the Radeon HD 7990 is 3482 and by the HD 7970 is 3482. Knowing that the shader performance of the Radeon HD 7990 is superior, it is not necessary to examine the GPUs' respective Texture and Pixel Fill Rates.
The Radeon HD 7970 Crossfire requires 460 Watts to run and the Radeon HD 7990 requires 375 Watts. We would recommend a PSU with at least 750 Watts for the Radeon HD 7990, but we do not have a recommended PSU wattage for the HD 7970. The HD 7970 requires 85 Watts more than the Radeon HD 7990 to run. The difference is significant enough that the HD 7970 may have an adverse affect on your yearly electricity bills in comparison to the Radeon HD 7990.
Can I Run It
|Core Speed||925 MHz||vs||950 MHz|
|Boost Clock||-||vs||1000 MHz|
|Architecture||GCN 1.0 Tahiti XT (x2)||GCN 1.0 Malta|
|Release Date||01 Jan 2012||vs||23 Apr 2013|
|GPU Link||GD Link||GD Link|
|Memory||6144 MB||vs||6144 MB|
|Memory Speed||1375 MHz||vs||1500 MHz|
|Memory Bus||768 Bit||vs||768 Bit|
|L2 Cache||1536 KB||vs||1536 KB|
|Delta Color Compression||no||vs||no|
|Shader Processing Units||4096||vs||4096|
|Actual Shader Performance||100%||vs||100%|
|Texture Mapping Units||256||vs||256|
|Texture Rate||236.8 GTexel/s||vs||243.2 GTexel/s|
|Render Output Units||64||vs||64|
|Pixel Rate||59.2 GPixel/s||vs||60.8 GPixel/s|
|Max Digital Resolution (WxH)||4096x2160||vs||2560x1600|
|Max Power||460 Watts||vs||375 Watts|
|Recommended PSU||-||750 Watts & 50 Amps|
|Recommended Processor||Intel Core i7-3770K 4-Core 3.5GHz||vs||Intel Core i7-3770K 4-Core 3.5GHz|
|Recommended RAM||8 GB||vs||16 GB|
|Maximum Recommended Gaming Resolution||1920x1080||vs||2560x1600|
|Mini Review||Radeon HD 7970 Crossfire is a solution of two Radeon HD 7970 put together using AMD'S Crossfire technology. |
Check the page of Radeon HD 7970 to know more about its chip.
Crossfire relies a lot on proper driver support and may suffer from micro-stuttering in lower frame rates (below 30). Benchmarks indicate the performance is overall, is up to 64% better than a single Radeon HD 7970 performing by itself but at times (depending whether or not the 3D game supports crossfire or in the graphics driver) it performed worse than a single Radeon HD 7970. Expect this combination to draw up to 600 Watt though the average power consumption should be slightly lower.
Even the most demanding games will run at the highest settings.
Radeon HD 7990 is a Dual-Graphics Solution based on the Graphics Core Next (GCN) Architecture.
The GCN Architecture succeeds the 40nm Terascale Architecture. In addition to being produced with a 28nm Technology, the GCN Architecture adds other Technologies that allow for energy efficiency. For example, ZeroCore Power, a long idle power saving technology, allows the Graphics Cards to shut down by itself when the Monitor is turned off.
GCN also adds Improved Anisotropic Filtering, DirectX 11 Tessellation and the Partially Resident Textures (PRT) Technology, which enables future games to utilize ultra-high resolution textures with the same performance as today's small and often repetitive textures.
It equips two GPUs Codenamed Tahiti XT which together have 64 Compute Units activated and thus offer 4096 Shader Processing Units, 256 TMUs and 64 ROPs. The Central Unit is clocked at 950MHz and goes up 1000MHz, in Turbo Mode.
Each GPU accesses a 3GB frame buffer of Fast GDDR5 Memory, through a 384-bit memory interface. The size of the frame buffer is adequate. The Memory Clock Operates at 1500MHz.
With a rated board TDP of 375W, it requires at least a 750W PSU with two available 8-pin connectors.
Radeon HD 7990 Competes with GeForce GTX 690 and proves to be considerably faster at resolutions over 2560x1600.
Radeon HD 7990 is best suited for resolutions up to and including 2560x1600. We recommend a Very Strong Processor (Intel Core i7 Quad Core/AMD FX Eight Core) and 16GB of RAM for Optimal Performance.
|Recommended CPU||Intel Core i7-4770T 4-Core 2.5GHz|
Intel Xeon E3-1270
Intel Core i7-2600K 4-Core 3.40GHz
Intel Core i7-2600 4-Core 3.40GHz
|Intel Core i7-4790S 4-Core 3.2GHz|
AMD Opteron 6278
Intel Core i7-980 6-Core 3.33GHz
Intel Core i7-3770 4-Core 3.4GHz
Intel Core i7-3770K 4-Core 3.5GHz
|Possible GPU Upgrades||-||GeForce GTX 980 4GB|
GeForce GTX 690
GeForce GTX 970 Gigabyte XTREME 4GB Edition
GeForce GTX 970 KFA2 EXOC Sniper 4GB Edition
GeForce GTX 670 SLI