Intel Core i7 (Nehalem)

[Scott Cairns]

The new i7 core CPUs are now available, hopefully the prices will drop in the not-too-distant future.

Anyway, I read about a really cool feature of the new i7 cores, in particular, it relates to programs that only utilise one core - the new chips have a way of engaging a 'turbo-mode' and making one core work superhard if it detects the other cores sitting idle.

Here a quote from the article;


Turbo mode, Engage!
The TDP (Thermal Design Power) of Nehalem is 130 Watts, which means that they are designed to make that much heat under heavy load. The problem with most applications today is that the CPU isn’t stressed across all four cores, leaving room for extra speed. Turbo mode provides that extra speed, actively increasing the multiplier of the CPU on-the-fly to provide a speed bump of a few hundred MHz while still remaining inside the TDP.

Of course, increasing all four cores is great when you’ve got a multithreaded application, but what if you’ve got a single threaded app? Well, those crazy boffins at Intel thought of that too. In the event that a single core is furiously working through a particularly demanding application, and the other cores are idly sitting there wasting power, Turbo mode can effectively power these idle cores down and increase the speed of the single core – and stay within the TDP – increasing performance in these applications when needed. This alone is probably the most important trend that we’ll see developing in the CPU design world, where the hardware itself will attempt to make allowances for inefficient or single-threaded programming.

Some of the music apps are going to get a great performance boost from this. The i7 cores also have a much improved caching system and more than one path to the ram now. (up to 3 I believe)

Full article is here; Intel Core i7 Extreme > CPUs, Motherboards & RAM > Build > Reviews > Atomic

[Scott Cairns]

No more front side bus;

QPI – A whole new FSBallgame
You’re probably familiar (if not intimately so) with the FSB. The FSB, or Front Side Bus, is a method of connecting all the components on a motherboard with each other. This has been used in all Intel motherboards up until this point, and has proven to be a limiting factor in increasing performance, bottlenecking the amount of data that can be worked upon. It is also not very extensible, as each CPU or component added to the system takes a slice of the total bandwidth available, reducing the benefits of having two. The FSB also requires a very high frequency (333MHz is very common), and can place stress on some motherboard components. It’s essentially an outdated tech, which has spurred on the evolution of the FSB’s replacement – the QPI.

The QPI, or Quick Path Interconnect, is similar to AMD’s HyperTransport, or HT bus. The HT bus is a bi-directional parallel link, and the last standard (3.0) provides a theoretical bandwidth of just over 40GB/s per second. QPI, along much the same lines, provides multiple links between each core of the CPUs, memory, and all the components on the board. Since this is not shared, each link is free to operate at the full bandwidth, allowing a core on another CPU access to memory data at a very fast speed. Current theoretical performance on an X58 motherboard of the QPI is just over 25GB/s. This might not sound like it’s as good as AMD’s, but here’s the kicker – this is between every major component on the board, in any direction, at any time. In terms of real-world usability and viability, the QPI is a significant improvement, and Intel will surely encroach heavily on the Server market once these chips become available.



Yeah! thumbsup

[Stisse]

I am also very interested seeing what kind of performance boost this new architecture will have. I read a review of the entrylevel 2,66 GHz i7 920 where it was compared to a couple of other CPU's (the QX9770 being the top end and Q9450 being the low end) and there was only one instance where the i7 didn't outperform the competition. Memoryintensive tests are where it really excels. I know it's merely numbers, but it sure looks promising.

Seeing that you already can get your hands on both the CPU and MB I would assume some of our more knowledgeable peers already have setups on their testbenches.


Cheers

[jcschild]

look here
Cores and VSTi the facts

[Stisse]

Originally Posted by jcschild

look here
Cores and VSTi the facts

Should've known you were on top of it already.

Thanks...

[A440]

There are rumours that early next year Mac Pro's will be shipping with i7 Nehalem processors. Anyone care to comment on this?

[jcschild]

LOL i cant even get an answer to what firewire chiset they are shipping mch les what proc is coming when....

my guess is they will have the new Xeons before the normal channel will.

[ekwipt]

the new Intel version of i7 definately has texas instruments firewire so does the gigabyte, but damn who knows what they'll put on the new macpro, i doubt they will take away firewire 800 from it, maybe firewire 400 will be non existent and they'll finally put esata plugs....

what I need in a new macpro (not that i'll be buying the i7 version) is another PCIe slot and higher bandwidth for the extra slots.

If I get everything i want in my current macpro, i cannot get a UAD card:

Video Card
Aja or Blackmagic card
Lynx sound card
Raid card

===== no more room