Video RAM - how much do you really need?
So how much do you really need then? Ah, the good old days of 4MB of EDO DRAM. Amazing that ten years of development have made it utterly useless - the main menu screen of Crysis needs 20x that amount of VRAM alone. Sharp-eyed readers may have spotted a common phrase throughout this piece: "a 256MB graphics card is not enough". This is certainly true if one wishes to play these titles at their maximum detail settings (and who doesn't?). We actually performed multiple examinations of the games, where we could (demos limit this somewhat), and the displayed figures are typical usage values. This does mean that there are parts where the memory demands are lower, and places where they're higher - either way, one is going to hit our displayed amounts at some point in the game, and thus affect one's experience. However, it doesn't necessarily mean that one's performance is going to be rock bottom, just because all the data won't fit into the local memory - the final frame rate of a game is determined by many variables, and if one of them is worse than the data swapping one then VRAM storage becomes less of an issue. That all said, most games are designed to be enjoyed with a certain level of visual quality and performance. Therefore, the recommendation for the minimum acceptable amount of memory on a graphics card is easy: don't take anything less than 256MB. It's just as easy for the maximum too: as much as possible. Don't be naive in thinking that games won't be using more than 512MB any time soon, because they already are in certain cases. We're still some way off before developers start making games that require half a gigabyte of video RAM to play properly, but if you want the best possible visuals, get the most RAM that you can. So, are we done then? No - in fact, there are two important caveats with that last paragraph. First, let's go back to the start of the article, where we spent a bit of time covering RAM technology and its development in speed. Accessing data quickly is very important, arguably more so than just pure storage, so if one is faced with a choice between two cards, for example, one that has double the RAM but half the speed of another, then one should nearly always go for the product with the faster memory. One can often find very large amounts of video RAM on mid-range to budget priced graphics cards, but consumers are certainly better off looking at the MHz values, rather than the MB ones. If you're plumbing for the latest, hot-snotting 3D beast, with as much RAM as possible, be prepared to encounter some additional problems, if you don't have enough system and virtual RAM to back it up with. Without going into all of the gory details, one needs to remember that rendering data is copied across from the system memory, not "cut n pasted". So a game that's using 300MB of video memory, just for things like texture buffers, is going to take that slice out of your system memory too. For 32 bit operating systems, there's also a limit to how much virtual memory a game can have, and there are many cases where a graphics card using lots of VRAM can eat into this limit so much, that it causes the game to run badly and even crash. Sometimes this can be fixed with patches, but for real solution to this, for the future, is to have a 64 bit operating system. The days when a PC's amount of system RAM was considerably larger than its graphics card's are long gone, just in the same way that CPUs are no longer second cousins to the GPUs power consumption, transistor count and die size. The blame, for want of a better word, lies solely at the feet of 3D games and their onward quest for ever-better graphics: if you think it's bad now, just wait to see what it's like in another ten years time.
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