Which ever you buy don't activate all the pre-loaded security software. Chose from the many free anti-virus available on the web. Then use MS Defender and I'd stick with the Vista Firewall.
I'd go for the Intel based system but I'm sure the AMD system would also be a good buy.
Lastly Acer offer extremely well priced 3 year warranty (don't buy third party stuff that's much more expensive) and I've bought mine for under £50 for my last two Acer laptops and had to use them in the 2 or 3 year. Acer pay for all courier costs and generally return the laptop very quickly. Take a look at click here
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