im always buying bits and pieces 2nd hand. what i do is work out if its worth buying 2nd hand vs the warranty. for eg if i can get a 1tb hd with 2/3 years on why would i buy a 1tb hard drive 2nd hand for £10 less. so do that with most parts unless its a very small budget pc.
warranty is mainly the reason to buy new.
warranty is mainly the reason to buy new.