I want to buy/build a PC that can do handle three 1920x1080 monitors. I don't mind if it's a 'single desktop' Eyefinity-stlye or extended across three in the normal multi-monitor fashion. I don't game and I don't need to watch HD video, it's really just a productivity thing for web/email/office etc.
I know a Radeon 5450 is supposed to do this, but does it, really? And what sort of underlying system would I need - could I make do with a fairly low-budget system, say Celeron Dual Core? What about RAM?
a single 5xxx series ati card would be the best bet. If your not doing gaming a 5450 might be all you need. Im not sure that when running such a high resolution that a better card will provide any improvement with desktop apps, maybe someone else can answer that. Running multiple applications at once, you would be better off with a lower end quad core cpu, something from AMD (athlonII x4)would be a good choice, and 2-4gb ram, depending on the applications you are using. This would make for a zippy office computer that will last you few years.