What's VRAM and MPEG?




I am thinking of buying a Pentium 166MHz with a 1.6Gb HDD with 16Mb of RAM, and a hex-speed CD-ROM drive with a sound card. This computer would be used for work and play. No doubt I will eventually be getting Windows 95 with related software. From what I've read, with a system like mine I should have a fast video card, but I am a bit confused. Could you explain in simple terms why I need a fast video card, and could you give me some explanations on these terms: Diamond Stealth 64 Graphics accelerator with 2Mb of VRAM, and MPEG?
- Simon Goeschl


Why do you need a fast video card? Because a slow one will be the speed-limiting factor when your system is trying to display images rapidly on the screen. This is especially frustrating in multimedia work.
VRAM is random access memory for storing video information. It is special purpose RAM with two data paths, rather than the usual one path of conventional RAM. The two paths mean that your display refreshes and the processor can be accessed at the same time, leading to a snappier all-round video experience. The system does not wait for one function to finish before the other starts, so video operation is faster.
MPEG stands for Motion Picture Experts Group, a group within the ISO (International Standards Organisation). What it actually refers to is a standard for storing a stream of compressed video/audio. There are two type of MPEG, MPEG 1 and 2. MPEG 1 is 25 per cent of broadcast quality (352 by 240 pixels) and is typically compressed at 1.5Mbit/sec. MPEG 2 is full broadcast quality (704 by 480 pixels at 30 frames per second in North America; 704 by 576 pixels at 25 frames per second in Europe). MPEG 2 is typically compressed at more than 5Mbit/sec.
- Ian Yates


Category: Hardware, Multimedia
Issue: Dec 1996
Pages: 154

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