Presumably your mobo doesn't have onboard temp sensors, as many (most?) do nowadays. In that case you have a couple of alternatives. Either way you'll have to get a separate temperature probe and readout, the question is what sort of level of sophistication do you want? You can get simple digital temperature meters with a probe that can slip between the cpu ceramic (not the actual core!) and heatsink - these can be got from radioshack I guess (I live in the UK, I think maplin stock them over here). The more expensive solution would be something like digidoc (i think it's called) which sits in a 5.25" drive bay slot and gives readouts from a number of temp probes that you can place wherever you like. Over here the prices are about £20 for compunurse (the plain digital readout style) or £40-50 for the digidoc drive bay thing. Of course if you went for the digidoc you could have one sensor for the cpu, one for the gpu, one for the mobo chipset etc - that's what I'd go for if it was me Sorry i can't point you to somewhere for certain that would stock either - but I guess http://www.2cooltek.com , http://www.leufkentechnologies.com and http://www.overclockershideout.com would be good places to start (though I think they're all more water/peltier cooling oriented).