Second-Generation Core i7
As with the previous generation of Core i7 mobile processors, the new models come in both dual-core and quad-core variants. But unlike before, the pleasant break-up between the dual-core and quad-core models is a bit murkier. Now, both dual-core and quad-core models exist in the same numerical series; Intel offers a Core i7-2620M and Core i7-2630QM. The only difference is the suffix. If the laptop you're looking at doesn't have the QM suffix in the processor name, it's not a quad-core processor!
The other naming convention to keep in mind is the last digit of the model name. If the last digit is an odd number (except for a 5) the processor is a low-power model with a lower clock speed and lower TDP. So the Intel Core i7-2635QM is a normal part; the Intel Core i7-2657M is built for ultraportables.
Confused? That's because the naming scheme is confusing. Just remember; if it ain't got a Q, it ain't a quad! And if the last digit is odd and not a five, the performance takes a dive while the battery thrives!
Note: The Intel Core i7 Extreme Edition is an exception. It is a quad, but it uses the XM suffix. You're not going to find that processor outside of high-end gaming laptops, however.
Otherwise, these processors all have similar features. They include hyper-threading, Turbo Boost, and Intel HD Graphics.