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Graphics Double data rate Gen1
RAM, or Random Access Memory, is a name used to describe graphics double data rate memory. The Graphics Double data rate Gen1 is typically a speed of 1-400 mhz. GDDR2 is usually between 400 mhz and 1250 mhz. GDDR3 is usually between 1066 and 2000 mhz. Basically, these numbers tell you the general speed of the RAM. GDDR is technically a description of the architecture used in the chip. Hence, DDRI1 ram cannot fit in any DDRI2 slots.
As a result of the fact that many other factors affect the actual performance of the video card, if you are considering buying and would like to know if Nvidia video cards use DDR3 while AMD/ATI use DDR5, then you do not have to worry about the memory as long as the card uses DDR3 or higher. A core processor should be your top priority. MSI RX 6750 has gddr6 memory module.
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GDDR Description
In general, GDDR DIMMs [GDDR-DIMMs] are similar to JEDEC standards for double data rate SDRAMs. This page covers the GDDR memory chips, which are typically found only on high-end desktop video cards. For a complete list of memory module types, manufacturers and descriptions, see the general Memory Module page. The GDDR1 module uses a 2.5 volt signaling system, while the GDDR2 module uses a 1.8 volt signaling system.
There are a variety of module sizes in standard JEDEC modules, ranging from 256MBytes to 8GBytes, with GDDR3 operating 1.5 times faster than GDDR2. A 300MHz clock enables GDDR1 to operate at 1.2Gbps, a 500MHz clock enables GDDR2 to operate at 2.0Gbps, and a 1GHz clock enables GDDR3 to operate at 9.6Gbps. The GDDR4 protocol is just now beginning to appear and provides an 18GHz bandwidth. A GDDR5 processor will operate at 5Gbps at 1.5 volts.
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