What video card should I buy with £100?

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Originally Posted by Wreford-Brown

I'm struggling to find the wattage of my system. Is there any way to dig the info out of the OS? I've physically looked on the outside of the tower but haven't yet taken the panels off.

It should be on your power supply, it's generally a big box located at the top and back of the system. You should be able to see it on the side if you look inside the system. Generally speaking, unless you bought a budget PC that saves on those things, you should have enough. Unless you have multiple HDs or other power-sucking devices, 450-500 watt (which is normal for most mid-range PCs) will be plenty enough for a new card. I wouldn't worry over it too much unless you have reason to believe that the PC's maker would've thrown a cheap, bad power supply on you.

As far as numbering, it's been a long time since I followed ATI's system, but with nVidia, higher number isn't neccesarily better.

Basically, you have a 4-digit number, of which the two first numbers are most important. The first number is more or less a 'generation'; the second number we can call 'series'. Generally speaking, any card that has #8## (2nd number an 8, e.g. 8800) is of the high-performance series for its' given generation; #6## is the mid-range card that has a good cost-for-performance ratio; and anything less than that is generally cheap budget cards which should be avoided for gaming purposes. A 9800 will most likely be a bit better than an 8800, but that difference may be less in terms of raw speed and more in terms of features on the card. An 8800 may actually be a bit faster than a 9600 (depending on make). Even an 8600 is certainly better than a 9200.

Overclocking - a video card, like the processor, can be overclocked to run faster, at the cost of greater power consumption, more heat being produced, and possibly increased instability. You can always overclock a video card yourself, if you are sure that you can keep it cool enough.
Some companies, such as BFG, ship their cards pre-overclocked - which is generally a good thing because they ship with added cooling that makes the card stable and cool even when overclocked. Generally the performance gain in pre-overclocked cards is not huge, but if the price difference between a non-overclocked and an overclocked card is none or small - the overclocked card may also be worth it. BFG's cards are generally pre-overclocked, but also come with lifetime warranty and have a very good reputation, so as long as an overclocked card is properly cooled it's not a liability in any way.

Which brings me to the next question - a brand does make a difference, but I would look more at features that come with the card than the brand itself. Generally a good video card manufacturer provides solid cooling and good warranty on the card at least. I'm not exactly rich so I couldn't exactly go around trying out all sorts of brands. I can vouch for BFG and XFX both being very reputable manufacturers with solid products. Had more than one card by both and zero problems. Their cards are well-optimized and have very good cooling. For others - I suggest you check reviews.

A good place to start if you're looking for reviews and comparisons would be here: http://www.tomshardware.com/

Also, a hundred pounds is not a bad video card budget! Personally, what I'd be looking at with that sort of money is probably an 8800 card. Prices on them have come down by a lot, yet they're still true performance cards that live up to today's standards very well.