Jonny - so, the processor comes first, then ram? Well in that case, the laptop that I linked to above seems good then, yes?
It has to do with the "weight" of the spec and how it applies to overall performance. For the most part, a slow dual-core will outperform a fast single-core. Single cores are very old & obsolete. You can do basic surfing and emails with them, but not gaming, video processing or anything else that is resource-intensive. You wouldn't run Win7 on a single-core machine. And a slow dual-core with a lot of RAM will outperform a fast dual-core with very little. These are imprecise ideas, but for a novice trying to buy a used laptop, they are good enough. My primary point is to advise you to not get too "spun-up" on insignficant details, while ignoring significant ones. Your first three questions are:
1) How much is it?
2) Is it single or dual-core?
3) How much RAM?
First thing to look at is price. Note, your 279 (Euro?) laptop converts to $384 US dollars, which is quite high for a used laptop (see below). You need to find out in this specific case what the word "refurbished" means. If it does not come with a good warranty, then it is no better than a "used" laptop and is therefore over-priced. Also make certain you can actually execute the warranty. If you have to pay for shipping & handling in both directions, and the list of covered defects is very limited, and they get to decide whether or not it's covered, have the final work and you have to pay to have them send it back to you (this happens), then I would buy somewhere else. There are plenty of used laptops, all over the world, and there is no compelling reason to purchase one from any particular source. It's a Buyer's market. Laptop's are high-risk and of uncertain resale value. You could pay $325.00 for a used laptop, then have it fall off the table and crash on the floor and be worthless for anything other than parts. You cannot rely on the idea that you can recover your investment as laptop are fragile and tempermental. They break for no reason at all.
Find out what a brand-new and low-end laptop costs. This is going to establish the high-end of your price range, as it makes no sense to pay more than 75% of a new laptop's price for a used one. There is risk involved in purchasing a used laptop. The Seller is selling it for a reason. There may be hidden problems that you do not discover until it is too late to get your money back. This is why a 1 week minimum, money-back guarantee is mandatory, and you need to make certain you are able to enforce it, if necessary. It's best if you buy the laptop at the Seller's house; that way you know where to go if there is a serious issue and they cannot feel secure in defrauding you. Understand, a fraudulant Seller doesn't know who you are either. You could be some kook that will come by and burn their house down if the laptop turns out to be a piece of junk. That is your power "edge" and it's a good idea to preserve it.
Here's a large list of dual-core laptops with 3 Gbytes RAM being sold new on NewEgg, except for note the refurbished $289 Compaq, listed from lowest price to highest:
http://www.newegg.com/Product/ProductList.aspx?Submit=Property&N=100006740&IsNodeId=1&PropertyCodeValue=393%3A60307%2C393%3A58096%2C393%3A60310%2C393%3A100612%2C393%3A28102%2C410%3A10742&bop=And&Order=PRICE&PageSize=20
These are being sold by the best online retailer on the planet, and these results are ideal. Anything better than these results comes with a certain amount of risk. As I said before, you are better off buying from a private individual in your home town, at there house and in person. You can negotiate directly, test it in their presence, get a 1 week warranty and know where to find them if they try to dodge you for a refund. This cuts out a whole lot of Sellers with bad intent, as they might be willing to cheat you, but not if it means they wind up with their throat cut in the middle of the front yard, while their pet chihuahua whimpers and frantically tries to dial 911.
