Chrome I'm sorry to say is horrible, and I hate saying it because many people prefer and rely on it.
What it is, is that chrome actually takes a larger CPU power than expected, recommend only multi core users with a combined amount of over 6GHz to use it tbh.
This is a problem which effects so many computers, it effected my old one, my brothers, my freinds & my mothers.
After testing it I did find it is NOT the fastest browser available the fastest is actually Maxthon followed by OPERA which are obviously not well known but like IE or Firefox does not demand a large CPU usage but OPERA & Maxthon are not known for their usability.
I personally recommend Firefox after testing the speed myself against others (such as google chrome, Safari & IE) this came up top after Maxthon & OPERA. Also if you download the addon DownThemAll then the downloads are faster then any of its competitors.