Hi there, I've just installed an extra 8gb of RAM into my late 2010 27" iMac. To check that the new RAM was working I ran the (extended) Apple Hardware Test, and got the following error code: 4MOT/4/40000003:HDD-1240 I've run the same hardware test a couple more times, and got these similar codes: 4MOT/4/40000003:HDD-1236 4MOT/4/40000003:HDD-1233 I've looked for solutions on various forums, but opinion seems to be divided as to whether these error codes mean there's a fan problem, a hard disk problem or a problem with the RAM. Does anyone have a definitive answer? And does anyone have any bright ideas about what to do about it, if anything? My computer appears to be running as normal. Everything is backed up. My warranty expired last month. If it's a case of taking it to an Apple store, does anyone have an idea of what they'd charge me to take a look at the problem? I live in the UK. Any help would be much appreciated. Thanks!