The Intel Graphics Media Accelerator (GMA) is a series of integrated graphics processors introduced in 2004 by Intel, replacing the earlier Intel Extreme Graphics series and being succeeded by the Intel HD and Iris Graphics series. This series targets the market of low-cost graphics solutions. The products in this series are integrated onto the motherboard, have limited graphics processing power, and use the computer's main memory for storage instead of a dedicated video memory. They were commonly found on netbooks, low-priced laptops and desktop computers, as well as business computers which do not need high levels of graphics capability. In early 2007, about 90% of all PC motherboards sold had an integrated GPU.
History
The GMA line of GPUs replaces the earlier Intel Extreme Graphics, and the Intel740 line, the latter of which was a discrete unit in the form of AGP and PCI cards with technology that evolved from companies Real3D and Lockheed Martin. Later, Intel integrated the i740 core into the Intel 810 northbridge. The original architecture of GMA systems supported only a few functions in hardware, and relied on the host CPU to handle at least some of the graphics pipeline, further decreasing performance. However, with the introduction of Intel's 4th generation of GMA architecture (GMA X3000) in 2006, many of the functions are now built into the hardware, providing an increase in performance. The 4th generation of GMA combines fixed function capabilities with a threaded array of programmable executions units, providing advantages to both graphics and video performance. Many of the advantages of the new GMA architecture come from the ability to flexibly switch as needed between executing graphics-related tasks or video-related tasks. While GMA performance has been widely criticized in the past as being too slow for computer games, sometimes being derogatorily nicknamed Intel 'GMD' (Graphics Media Decelerator) and being essentially referred to as the world's first "graphics decelerator" since the low-performing S3 ViRGE, the latest GMA generation should ease many of those concerns for the casual gamer. Despite similarities, Intel's main series of GMA Integrated Graphics Processors (IGPs) is not based on the PowerVR technology Intel licensed from Imagination Technologies. Intel used the low-power PowerVR MBX designs in chipsets supporting their XScale platform, and since the sale of XScale in 2006 has licensed the PowerVR SGX and used it in the GMA 500 IGP for use with their Atom platform. With the introduction of the Platform Controller Hub, the Graphics Media Accelerator series ceased, and the CPU-based Intel HD and Iris Graphics series was created.
GMA Generation 3
GMA 900 The GMA 900 was the first graphics core produced under Intel's Graphics Media Accelerator product name, and was incorporated in the Intel 910G, 915G, and 915Gx chipsets. The 3D architecture of the GMA 900 was a significant upgrade from the previous Extreme 3D graphics processors. It is a 4 pixel per clock cycle design supporting DirectX 9 pixel shader model 2.0. It operates at a clock rate ranging from 160 to 333 MHz, depending on the particular chipset. At 333 MHz, it has a peak pixel fill-rate of 1332 megapixels per second. However, the architecture still lacks support for hardware transform and lighting and the similar vertex shader technologies. Like previous Intel integrated graphics parts, the GMA 900 has hardware support for MPEG-2 motion compensation, color-space conversion and DirectDraw overlay. The processor uses different separate clock generators for display and render cores. The display unit includes a 400 MHz RAMDAC, two 25–200 Mpixel/s serial DVO ports, and two display controllers. In mobile chipsets, up to two 18-bit 25–112 MHz LVDS transmitters are included.
GMA 950 The GMA 950 was the second graphics core produced under Intel's Graphics Media Accelerator product name, and was incorporated in the Intel 945G chipsets. The processor includes an up to 400 MHz 256-bit core, supporting up to 10.6 GB/s memory bandwidth with DDR2-667 system RAM, up to 224 MB max. video memory through DVMT scheme, 1.6 GPixels/s and 1.6 GTexels/s fill rate, a max. resolution of 2048x1536 for both analog and digital displays, 2 SDVO ports for flat-panels and/or TV-Out via ADD2 cards or media expansion cards. 3D-wise, GMA 950 supports up to four pixels per clock rendering, Microsoft DirectX 9.0 hardware acceleration & Vertex shader 3.0 and OpenGL 1.4 with ARB extensions on Windows.
GMA 3100 Integrated graphics found on Q33, Q35, G31 and G33 chipsets. It supports Pixel Shader 2.0 with OpenGL 1.4, but Hardware Vertex Shader isn't supported.
GMA 3150 Found in Intel Atom D4xx, D5xx, N4xx and N5xx (codenamed Pineview) processors. Like GMA 3100 and GMA 3000, this is a very close relative of the GMA900/950, completely different from the GMA X3000 series. Supports up to 384 MB video memory (Using the Windows XP driver), DirectX 9.0c, Shader Model 2.0, OpenGL 1.4 with Microsoft Windows and OpenGL 2.1 with Linux.
GMA Generation 4
GMA 3000 The 946GZ, Q963 and Q965 chipsets use the GMA 3000 graphics core. The GMA 3000 3D core is very different from the X3000, despite their similar names. It is based more directly on the previous generation GMA 900 and GMA 950 graphics, and belonging to the same "i915" family with them. It has pixel shaders which only support Shader Model 2.0b features, and the vertex shaders are still software-emulated. In addition, hardware video acceleration such as hardware-based iDCT computation, ProcAmp (video stream independent color correction), and VC-1 decoding are not implemented in hardware. Of the GMA 3000-equipped chipsets, only the Q965 retains dual independent display support. The core speed is rated at 400 MHz with 1.6 Gpixel/s fill rate in datasheets, but was listed as 667 MHz core in the white paper. The memory controller can now address a maximum of 256 MB of system memory, and the integrated serial DVO ports have increased top speed to 270 Mpixel/s.
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