I have a friends Dell Latitude laptop which needed the HDD & CD ROM replacing (all done, no problems) but it suddenly suffered a 90% RAM failure in that the BIOS only reports back 12Mb of RAM from a 128Mb chip and a RAM diagnostic program shows lots of failures under test conditions. The unit will start, report the RAM anamoly,F1 to continue etc, but then trying to start the OS stresses it too much (as you would expect) and it locks up. There is a noticeable increase in temperature at various specific locations on the underside of the case, one being the RAM compartment. The small cooling fan visible from the rear isn't spinning at any time, but my wife's fan (similar Dell laptop) doesn't spin all the time either. Replacing the RAM with a fully working chip returns the laptop to proper working status with the exception of the fan, this results in the eventual build up of heat which in turn causes it to slow down then lock up. My experience of failed fans is that they are stiff to rotate (usually) when failed. This one isn't, a quick blow will send it spinning for a few seconds although it doesn't seem power assisted or making any effort to spin. The problem at the tip of the iceberg is obviously the cooling. Are Dell laptop fans supposed to spin from power up or are they thermostically controlled? A replacement fan is only about £35, but might these be symptoms of a failure of the motherboard too? Can overheating cause a partial failure of the RAM chip? The fact that the wifes Dell's fan doesn't spin 100% of the time has me querying my diagnosis and I don't want to spend £35 of my mates money if the problem is really the mobo. Any thoughts appreciated.