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[directhex]

Does any one no where i can purchase these components in the UK?

Sure.

Here's an example, a quad-core ARM chip from Freescale for £33: http://uk.farnell.com/jsp/search/dis...sp?SKU=2253171

It's got 624 pins. You'll need to design and press your own motherboard, and solder the chip to it.

Here's a corresponding 1GB RAM chip: http://uk.farnell.com/hynix-semicond...bga/dp/2147278

And 2GB of flash storage. You might want more than one of these. http://uk.farnell.com/hynix-semicond...sop/dp/1712425

[watercooled]

Does any one no where i can purchase these components in the UK?

You're missing the point - these parts don't just slot together, nor are they readily available at retail. There are practical reasons computing systems this small are not user serviceable.

What's with the desperation to build? Realistically, as has been said already, your options are something like a mini-ITX build with replaceable CPU etc, or the next step back would be some compact barebones system like the NUC/BRIX/etc where you can add storage/RAM.

Either that, or drop the DIY requirement and just buy one of the other pre-built devices suggested. But don't expect desktop performance. Another option would be to buy a tablet of course.

It may be worth paying some attention to the advice given rather than selectively ignoring it; what you're after (although I'm not entirely sure what it *is* you're after) may be possible, but not at the price or complexity you seem to have in mind.

[BobF64]

If youre just trying to build a computer as some sort of project, the only realistic way is to build something simpler than current consumer grade PCs, something like the old Z80 based computers of the late 70s and early 80s.