Basic (but upgradable) PC

Averaged

I'm looking for a reasonably basic PC for the usual web/office tasks, plus some simple gaming for the kids (Minecraft/Terraria). In the past i've used simple all-in-one's like the Acer Revo and Zotac Zbox, but this time i'd like something that allows at least some upgrade potential in the future, e.g. a £50-£100 Nvidia graphics card for some slightly more graphical games, a bit more memory, etc.

I'm happy enough putting together a 'barebones' type system myself but it seems that a basic i3-based system will likely cost £300-350 once i'm up and running (adding hard disk, memory, integrated graphics for now - I have a spare keyboard/mouse/monitor already, and can get a legit Win 8.1 and Office licence for very cheap via work). That's £50-100 more than i'd really like to spend, and was wondering about something like this

http://www.amazon.co.uk/Zoostorm-7270-8037-5700-3-4GHz-Windows/dp/B00QRRZDNO/

which is about the price I want to pay (£250) and still looks to have some upgrade potential. However, I know little about this area of the market these days and so i'm not clear if the specs are worthwhile (AMD A10 5700 Quad Core 3.4GHz Processor and AMD Radeon HD 7000 Series graphics). Is it a false economy over going for i3/i5 level? Or will the AMD be fine for what I want?

Any other suggestions for what to look for around the £250 mark?

Nearlyold

Why not buy a refurb for example you can get a Dell Optiplex 755 SFF CORE 2 DUO 2.6 Ghz X 2 (5.6GHZ) for £74.99 from the likes of Compuclear in Stourbridge (I've no connection with them but have purchased from them in the past and had no problems). Obviously you'll pay more for a higher/later spec.