What is RAM?
RAM all told It’s Varied Splendor
In a number of the previous sections, you have examined the varied RAM architectures and designs. During this section we’ll gift to you, the curious shopper, and info regarding the varied styles of RAM used for special functions. You have in all probability detected terms like Video RAM and Rambus, however does one recognize what they mean? Does one care?
If you do, here we tend to shall enlighten you seekers of truth……
Video RAM may be a form of RAM used on video cards, and is employed solely for video calculations. VRAM stores peel values for a graphical show, and therefore the board’s controller reads these incessantly because it refreshes the show. This enables for higher video performance while not overloading the CPU with an amazing quantity of computer screen info.
VRAM is dual-ported, as hostile DRAM and SRAM, that each has single access ports. This suggests that VRAM has double the information measure of either SRAM or DRAM, and leads to quicker video performance.
There square measure various sorts of video RAM, every used for its own special case. SGRAM may be a in no time style of VRAM utilized in 3D accelerator card. Windows RAM is specialized for graphic performance, with roughly twenty fifth a lot of information measure than VRAM.
Rambus Direct Memory
Rambus is that the newest, hottest style of RAM starting on the market. Developed by the Rambus Corporation, Rambus Direct RAM guarantees to be quicker than current memory modules, and can incorporate several options helpful for memory intensive computations, like 3D interfaces, interactive games, and streaming transmission. RDRAM are used with Intel microprocessors starting in 1999. Consecutive pc you purchase can possibly use RDRAM. So why is it thus great? Well, think about it in these terms: from the previous sections, you recognize that EDO DRAM works at speeds of regarding eighty three.3 megacycles. SDRAM, the present speed businessperson of RAM, supports bus hastens to a hundred megacycle. Not bad. However this piddle compared with the speeds RDRAM boasts: bus speeds of up to 267 MHz! RDRAM can synchronize itself to the CPU bus, as high as 133 megacycle.
RDRAM provides a pair of computer memory unit bus, as hostile DRAM’s one computer memory unit bus. With a peak RAM speed of 800 megacycles, RDRAM can do information transfer rates of one.6 billion bytes per second! RDRAM conjointly uses pipelining to maneuver information to cache memory nearer to the CPU and show devices, additional enhancing system performance.
OK, so you, the educated shopper, square measure at a pc fair trying to expand the RAM on your card. Right now, you’ve got a pair of 8-meg chips on the board, and you would like to by a pair of a lot of to bring your machine up to a smashing total of thirty two. Whereas you are wandering the fair, you see a commercial for RAMBUS RAM chips. Now, you are eyeing the advertisement, thinking, “Man, I will get one 32-meg chip, and since it runs at a better speed, it will be higher overall for my machine!” You scrutinize the worth and GADZOOKS! It’s $350 a chip! 2 8-meg EDO chips would solely value regarding $40!
OK, hotshot, what does one do? Do a speed comparison between the sixty six megacycle EDO chips and therefore the 267 megacycle RAMBUS chip. Is that the acceleration in proportion with the number of cash you’d got to pay to urge the chip?
- Well, first, let’s do a speed comparison. Since everything else is equal, we tend to do a acceleration equation, with all things however the clock rate cancelling out.
———- = four.05 times quicker.
OK, thus currently we all know what proportion quicker it’s. Now, is it proportional? Well, i select to appear at this as what proportion am I goanna pay proportionately. Ignoring the actual fact that you are shopping for sixteen Megs as hostile thirty two, we are able to set it up as:
——— = ~8.75
So, can we play regarding nine times a lot of for four times the performance?. in all probability not….