Does the Intel i7 offer real improvement over its predecessors? [closed]

Solution 1:

Definitely does. You want to talk about Nehalem first, the quad-core should be discussed after that.

• Start from the Wikipedia notes on Nehalem
• ArsTechnica articles -- What you need to know about Intel's Nehalem CPU
• Intel's Nehalem simply sizzles -- Don't go by the title, but do look at the points
• With i7, soon you will say ta-ta to the North Bridge even on your laptops!

A very quick summary from the ArsTechnica article.
Nehalem-derived processors — if it's still appropriate to call them "processors" and not "systems-on-a-chip" (SoCs) — will mix the following elements in different proportions, depending on the platform and product:

• Number of cores
• Number of memory channels on the integrated memory controller
• Type of memory supported (registered and unregistered DDR3 or FB-DIMM)
• Number of links in the QuickPath interface (for scaling QuickPath bandwidth)
• L3 cache size
• Power management features
• Integrated graphics [we are talking on-chip here]

References.

• Details: Inside Nehalem: Intel's Future Processor and System
• More details: Intel Core i7 (Nehalem): Architecture By AMD?
• Some more: The Nehalem Preview: Intel Does It Again
• About quad-core: CPU Cores: The more the better?
• If you are counting cores -- Intel touts 8-core Xeon monster Nehalem-EX
• Nehalem News blog -- been silent for some time now, but has info collection
• Some performance comparisons -- Istanbul VS Nehalem VS Harpertown, Jul 9, 2009
• InfoWorld -- Nehalem workstations: A new era in performance, Jul 9, 2009

Solution 2:

There are certainly lots of changes and improvements, it's not just marketing speak, there are genuine improvements. I haven't tried one personally, but there are two features that I would consider looking at for potential performance gains:

1) Re-implemented Hyper-threading. Each of the four cores can process up to two threads simultaneously (with some restrictions), so the processor appears to the OS as eight CPUs. Hyper threading was in the old P4s, but this is the first time intel have introduced hyper threading into their core architecture.
2) "Turbo Boost" technology allows all active cores to intelligently clock themselves up in steps of 133 MHz over the design clock rate as long as the CPU's predetermined thermal and electrical requirements are still met. This sounds like a great idea, you get small increases in clock speed automatically and safely. Way better than over clocking manually.

There are also lots of efficiency improvements (both to power and processing) that should have a positive effect.

(See Wikipedia)

Whether these improvements will actually translate to any significant physical boost in speed is hard to tell and probably partly down to the kinds of applications you run. Initial tests certainly seem to indicate that they outperform the top end of the previous generation of CPUs from intel (See here. Look at the difference in score between the old "Intel Core 2 Extreme QX9770" and the new "Intel Core i7 965 Extreme". in fact even the lower end i7 920 out performs the top end Core 2).

It uses a new socket that is incompatible with the old style, the slight cynic in me says that they are just making small incremental improvements and breaking compatibility each time to keep the market moving and buying new gear. But this is nothing new.