My brother bought a refurbished Mac Mini online a few weeks ago, it was working fine up until a few days ago when it started to give him a plain grey screen at power on, but it never gets beyond that. He put the Leopard DVD in to see if he could boot from that, but it still stays at the grey screen and the disc just keeps spinning and DVD drive is very loud. He tried some potential solutions I found online for him from Apple but none worked. So my question is, if he brings it into the Apple Store will they exchange it on the spot since it's under 90 days, or since it's a refurb will they not do an exchange, and instead only offer repair service? Thanks.