I have my wife`s notebook:
Fujitsu Siemens Amilo Pro V3515 + Core2Duo T5600 + 2GB DDR2 667Mhz + HDD WD@160GB
And, got dammit, i have same problem, indeed. It`s make me cry - she cant watch Youtube or smth else, like that. Couse after 5 min - it going freeeeeeze.
Any suggestions?