My brother just got a system on very friendly terms, free actually. When it works, life is good. System does all that the users require. Unfortunately, it shuts down after a while. I installed MBM. This shows that the CPU temp starts at about 40C and steadily increases until 70C and shuts off. It sounds like a problem with the HSF. The current one was made by aopen. It is about an inch of aluminum with a no-name 60mm fan (label fell off?). There is a free 80mm fan space on back of the case. I checked dansdata.com(see index) and overclockers.com for input. Great sites, way too much information. Some of the offerings were scary, like the one by Thermalright that requires you to dismount the MB to install! Decided that some expert advice was in order. Thank you in advance. The components are: a1ble mid tower - ugly but it works hec 250 watt PS - *shudder* aopen MK77-8XN - micro ATX MB AMD 2500+ CPU - woohoo! 40 GB drive, floppy, CD-R 256 MB PC2700 RAM (KVR?) 32 MB video card My questions: 1) Any recommendations for a new HSF? Moderate noise is fine. Nobody sleeps in same room. $50 is budget target. System will be in upper story (warm). MB has two clips (L/R). MB is cramped for space so 60mm base is about the most that will work. With any luck I will be seeing less of this system (limited travel). 1A) Any recommendations for an 80mm exaust fan? 1B) Does anyone use filters for fans anymore? Lots of dust bunnies in the environment. 2) Any recommendations for a new PS? I'm thinking that 400 watts or so should be fine. $75 budget target. 2A) A lot of power supplies have a fan in 'back' and another on 'top' or 'bottom'. Does the orientation of PS matter? No fan hole on top of case. His kids probably use the case as a cup/soda holder. 2B) Any thoughts of the goodness/badness of the Antec SmartPower line vs the TruePower line? 3) Is there any problem with putting different vendor RAM in if the clock speed (PC2700, cl2.5) is the same?