windows 7 – Lightweigh browser for laptop with AMD Athlon Neo X2 processor

I need a Lightweight browser for the MSI x430 laptop. this laptop has an AMD Athlon Neo X2 processor that has 1 core and 2GB of RAM so when I open chrome or Firefox on it the cpu goes to 100%.
I’ve installed midori on it and it can’t even open it.
Please let me know if there is any Lightweight browser that this laptop can run it without making cpu 100%.