The rollout of the LGA1156 platform was welcomed by most computer users and reviewers. Rid of unnecessary architectural excesses of the LGA1366 in a common computer, the new platform has become simpler and cheaper and presented the Nehalem for the masses, which people had waited for so long. And the future launch of new dual-core processors for this socket will apparently add popularity to this platform, lowering the club entry fee by another $100. It goes without saying that the new Core i5, i3, and Pentium processors will not demonstrate miracles of performance, as two cores (even if spiced up with Hyper-Threading) is a bare minimum these days. But we don't expect these processors to break records. A lion's share of CPU sales, especially ready systems, falls to the price range below $200, where competition is getting increasingly sharp. In the past, manufacturers would let only cut-down or outdated processors into this segment. And now AMD, for example, focuses on this segment, offering its users Athlon II processors with the excellent price/performance ratio. However, Intel LGA775 solutions (provided they have similar prices) can compete only with the lower solutions from the latter, namely Athlon II X2, abandoning the most interesting field (from the point of view of the mass market, not enthusiasts, of course) to Athlon II X3 and X4 practically without resistance. Appearance of new processors will lead to aggravation of competition and will allow to give up LGA775 painlessly in most market segments. However, this will happen in future. As for now, we continue to examine interesting aspects of existing processors for LGA1156.

But before we proceed, we should make another little digression, which is too small for a separate article. After publication of the first performance tests many of us asked ourselves a question -- what's the point in Core i7 870, if the equally-priced Core i7 950 (for LGA1366) works faster?When the Core i7 960 was launched and occupied the same price range, there appeared even more baffled questions. This processor is really necessary. First of all, it's for large manufacturers, not for individual users. The fact is, TDP of the CPU+chipset combo for non-extreme Core 2 Quad models is about 120W, only 100W for LGA1156 Core i7. And it exceeds 155W for the LGA1366 platform. In other words, if you are a large system integrator, and you have a line of computers based on Core 2 Quad, it can be upgraded to the modern platform, you only need to change processors and motherboards. And coolers, of course. Fortunately, requirements to their retention modules haven't changed much. However, it's not a problem for motherboard manufacturers -- some motherboards support both old and new coolers. And if you want to manufacture computers based on the top series, there will be different requirements to a power supply units, to PC enclosures, and to coolers. It's not a problem for enthusiasts -- parameters of all these components are selected with a large safety margin, while the situation with big manufacturers is different. For these very manufacturers, the company will produce low-power processors with the wonderful TDP of 82W. That's not a significant reduction. But no necessity in the Northbridge allows to use these processors in all systems designed for Core 2 with the TDP of 65W (Core 2 Duo and low-power Core 2 Quad). And what about individual assemblers, what do they gain? Nothing, actually. Even coolers will probably be the same for LGA1156 and LGA1366. So if you are ready to buy a processor in this price range, our recommendation is simple: if you are happy with a full-size ATX PC enclosure and want to get maximum performance, take a look at Core i7 960. If you need a compact computer, consider Core i7 870. It would have been nicer to see equally-priced processors to have similar performance levels, but performance is only one of characteristics these days. The one and only for some people, and not quite so for the others.

However, $600 processors (disbursing price - $562) are designed for selected few, regardless of the platform. The other people are very optimistic about the Core i5 750: with its disbursing price of 194 dollars, it demonstrates performance on the level with top models for LGA775 and Socket AM3. Fortunately, it comes with practically all architectural improvements of Nehalem and the same four cores as the top processors in the series. However, "practically all" is not the same thing as "all" -- in particular, this processor does not support Hyper-Threading. People's attitude to this technology varies. But we cannot deny that it provides significant performance gains in a number of applications, and it'll be irrational not to use them. Besides, Core i5 750 does not support VT-d. As far as we know, XP Mode inWindows Seven cannot use this technology anyway. But some "serious" virtualization technologies (Xen in particular) can squeeze benefits from it. It's necessary only to some users.What if you don't want to give up Hyper-Threading and VT-d? In this case your choice is Core i7 860, which supports it all. However, it costs $284 in large shipments, that is it's $90 as expensive as Core i5 750. It's not that much compared to the overall PC costs. But if we consider processors only, 1.5 times as expensive is no picnic. Core i7 860 is faster than Core i5 750 by 133 MHz, but this difference is easy to compensate -- just raise the bus frequency by 7 MHz (it's not even overclocking, especially as it can be done with most retail motherboards automatically).

Is there an alternative? Actually there is, as Intel presented on September 8th not only desktop processors in this design, but also Xeon 3400. However, the cheapest processor in this series (Xeon X3430) is not a very interesting product -- it supports VT-d, but it does not support Hyper-Threading. Top Xeon X3460 and X3470 processors do not interest us either, as they are more expensive than Core i7 860 and 870. But the X3440 and X3450 may be a very interesting choice -- they support the same technologies as Core i7 800, but the former costs only $215, the latter -- $240. It's apparently better to add $20 for Hyper-Threading than $90.

Do these processors have shortcomings? Yes, they do. For one, clock rate: 2.53 GHz and 2.66 GHz correspondingly. For two, UnCore multiplier equals 16, which gives us 2.13 GHz (like in Core i5 750) instead of 2.4 GHz (Core i7 860/870). For three, maximum memory multiplier is 10 instead of 12: just like in Core i5 750. And the boost mode works as 4-4-1-1. Finally, QPI bus provides only 4.27 GT/s. However, frequency can be increased by overclocking, and lower multipliers of UnCore and QPI will be an advantage in this case, facilitating the process. If you overclock this processor, it makes sense to disable Turbo Boost, and memory just does not need multiplier 12 -- with the reference clock rate of 200 MHz even 10 is sufficient for DDR3-2000, and DDR3-1600 (which a more probable choice for a thrifty user) needs only 8.

However, Xeon has a certain advantage -- it supports registered as well as usual non-buffered memory. The former is slower by 5%, and it's more expensive. Different options are available though -- for example, non-buffered DDR3-1333 memory modules (4GB) are three times as expensive as some registered memory modules. In return, you can install up to 32GB of registered memory (versus 16GB of non-buffered memory). For two, such memory is supported even as three memory modules per channel -- good news for those people, who bought (or going to buy) P55-based motherboards with six slots (like Gigabyte P55-UD6). Considering the present prices, 24GB of memory in this case will be less expensive (almost by one and a half) than non-buffered memory for LGA1366. It's pennies from heaven for some users. Just make sure your motherboard does recognize registered memory -- the controller is integrated into a processor, of course, but we have seen compatibility problems many times.

Testbed configurations

Theoretical similarities and differences are an interesting topic, but we are more interested in performance, and this needs testing. For this very purpose we got a Xeon X3450 from Intel. This processor will be compared with three competitors manufactured at the same plants:

This is not a random selection. In fact, in terms of X3450 performance it's Core i5 750 + Hyper-Threading, so direct comparison of these contenders suggests itself. Core i7 860 is the next step: another 44 dollars (that is it's more expensive than our Xeon by as much as the Xeon is more expensive than the i5 750), but we get higher clocked cores and UnCore. And Core i7 920 is interesting as a lower representative of the LGA1366 series, many of its characteristics resemble those of the X3450.

To be as objective as possible, we used the same memory kit on all platforms, having given up the idea of three channels on LGA1366 (especially as we already found out, that it's useless in terms of higher performance). Memory frequencies are different, because Intel DX58SO does not allow to use Core i7 920 with DDR3-1333, limiting the processor to the official DDR3-1066. And it makes no sense to artificially spoil the life of LGA1156 processors (which officially support DDR3-1333).

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