According to the specs I have been able to find on this model of laptop you should be able to use a max cpu model of T9500 Core2Duo which is the 2.6Ghz Dual Core Cpu. Newegg sells the T9300 which is a step down but only 100 mhz slower at 2.5Ghz New
http://www.newegg.com/Product/Produc...82E16819111001 for $329.00 w/free shipping it looks like. If you are looking for a new CPU. Otherwise I would look on e-bay for other versions of the CPU you can find CPU's fairly cheap on ebay just make sure you dont get ES versions which are samples that could contain glitches. I just bought a T9500 to replace the T7500 in my Vostro 1500 in my sig and it works perfectly and wasnt that difficult to replace either. If you are looking for inexpensive its hard to get cheaper than an ebay deal just make sure they have a return policy and/or warranty even if its only 30 days and make sure they have a decent number of positive feedback as well Im sure you can get a feel for their trustworthyness by reading a few of the feedbacks maybe. If theres anything else I can help you with let me know.