Intel Notebook Processor - Need Help Deciding (2720QM or 970)

New member (long time reader) and first time poster... so go easy on me.

I have a few questions regarding the difference between the following notebook processors:

- Intel® Core™ i7-2720QM Processor (6M Cache, 2.20 GHz)
- Intel® Core™ i7-970 Processor (12M Cache, 3.20 GHz, 4.80 GT/s Intel® QPI)

Differences:
- Clock Speed / Max Turbo Speed (negligible)
(2720QM) 2.2GHz / 3.3Ghz
(970) 3.2GHz / 3.46GHz
- Cache
(2720QM) 6MB
(970) 12MB
- No. of Cores / Threads
(2720QM) 4 / 8
(970) 6 / 12
- Max TDP
(2720QM) 45W
(970) 130W
- Memory Type
(2720QM) DDR3-1066/1333/1600
(970) DDR3-800/1066

Ok, so now on to the questions. This notebook will be used primarily for gaming (more specifically, MMO's).

(1) What is the difference between a notebook processor (2720QM) and a "desktop" notebook processor (970).

(2) Cache - Will I notice a 6MB increase in cache? If so, is it SIGNIFICANT?

(3) # of Cores/Threads - Same question as above, will the additional cores/threads provide a significant increase to gaming performance?

(4) TDP - I see the TDP is much higher (almost 3x) for the 970, but what does that mean (higher = better)?

I'm not necessarily sold on either of the above processors. If someone feels that the 2630/2820 or the 960 would better serve my goals, please speak up! Thanks in advance for the assistance. GREAT FORUM!

 

1. The biggest differences are heat, power consumption, and manufacturing process. the 970 is a last gen desktop processor and is rated at 130w TDP at 45nm. The 2720qm is only 45w TDP (almost a 1/3 less power usage) and 32nm. Basically, mobile processors are much more power efficient and produce less heat than their desktop cousins.

2. Yes, the increase in cache will help, but the change in architecture to the sandy bridge 2720qm will probably offer more improvements other than cache to narrow the margins. This article (though dated) is a good explanation of cache sizes:

Does Cache Size Really Boost Performance? : What Is The Impact Of Cache Size?

3. Only in games/applications that make use of it. Most games are just starting to use quad core fully and very few use hex core. However, many applications (zipping, encoding, editing, etc) can use all the cores/threads and you'll see a pretty sizeable difference. (50% better performance when using all the cores on the 970 versus the 2720)

4. TDP is "thermal design power"- which is simply the maximum power rating of the processor. It's only useful when you combine it with benchmarks because a part at 45w now can easily beat some two year old parts at 130w. Higher TDP means more heat is generated due to the higher power draw. In a mobile environment, this leads to a larger and potentially louder machine (to run the cooling).

Mobile Processors - Benchmarklist - Notebookcheck.net Tech