13-06-2012, 02:00 PM
It happens every year, almost like clockwork—literal and figurative:
Intel implements one or the other part of its tick-tock development
strategy, which guarantees processor innovation is an ongoing, rather
than an intermittent, process. But whether any given year is the tick (a
reduction in the production process) or the tock (a new
microarchitecture), it can occasionally be difficult to know exactly
what's changed, or what impact it will have on you. So if you've been
wondering about the differences between Sandy Bridge and Ivy Bridge,
respectively Intel's second- and third-generation Core processor
technologies, here's a list of the most important differences—and
similarities—between the two.
1. Sandy Bridge is last year's news. Intel
introduced its Sandy Bridge desktop and laptop processors at the start
of 2011, just in time to coincide with the Consumer Electronics Show in
Las Vegas. Ivy Bridge, due to a number of delays, arrived in April of
2012, and essentially replaced Sandy Bridge in the market. This doesn't
mean you won't still find Sandy Bridge processors, or systems using
them, for sale in some places, but they're more or less in their
end-of-life cycle now, with the newer technologies and benefits of Ivy
Bridge having replaced them.
2. Ivy Bridge is a "tick," Sandy Bridge was a "tock."
With its Sandy Bridge chips last year, Intel introduced a new
microarchitecture that changed the building blocks of the processor's
operation. Because Ivy Bridge uses the Sandy Bridge architecture, just
about each individual change Intel debuted before (Turbo Boost 2.0 for
dynamic hands-off overclocking, Quick Sync Video for speedier video
transcoding, and so on) also applies now. The changes this time around
are far less sweeping, with the processing die shrink from 32nm to 22nm
being the biggest news. Intel has added some additional features as
well—enough, in fact, that for a while the company referred to this
year's move as a "tick-plus"—but this is the most fundamental.
3. Ivy Bridge uses some newer technologies.
In order to achieve the reduction in Ivy Bridge die size, Intel
developed a new kind of three-dimensional "Tri-Gate" transistor. But
there are some additional advancements in Ivy Bridge, as well, including
support for PCI Express (PCIe) 3.0 and DDR3L (low-voltage) memory,
buffed-up security features, and better integrated graphics (see below).
4. Ivy Bridge is faster—but just a little.
Performance generally improves more between "ticks" and "tocks" than
between "tocks" and "ticks," and you can see this in the relationship
between Sandy Bridge and Ivy Bridge. In our testing, for example, an
Intel Core i7-3770K Ivy Bridge processor earned in our CineBench R11.5
multicore rendering test a score of 1.65, compared with a Core i7-2700K
(the fastest Sandy Bridge chip) in the same system earning 1.58. The
chips' scores in PCMark 7 (3,679 versus 3,867) and times in Adobe
Photoshop CS5 (2 minutes 47 seconds versus 2:50) and Handbrake 0.9.6 (32
seconds versus 31 seconds) also bear this out. So you will see speed
bumps, but they'll be small this time around. Chances are, however, that
next year's "tock" will boost the speeds of new processors considerably
5. Ivy Bridge uses less power. With
die shrinks typically also come a reduction in the amount of power that
processor needs to operate. That's certainly true in the case of Ivy
Bridge. As long as we were testing the Core i7-2700K and the Core
i7-3770K with otherwise exactly the same hardware setup, we decided to
take some power readings using an Extech Datalogger. Though the full
systems idled at almost the same electricity draw (about 71 watts),
there was a stark difference when we maxed out all four of the
processors' cores: The Core i7-2700K system needed 166.5 watts, but the
Core i7-3700K drew only 136.3—a remarkable change.
6. Ivy Bridge has better graphics...
Sandy Bridge processors sported a redesigned video system (available in
two flavors: Intel HD Graphics 2000 or 3000, with the latter being more
powerful), but one that was limited in a few key ways. Ivy Bridge chips
removed one of the chief limitations by replacing Sandy Bridge's dusty
DirectX 10.1 (DX10.1) support with DX11 capabilities, and generally
improving their speed and functionality. We didn't see enormous frame
rate leaps between HD Graphics 3000 (in the Core i7-2700K) and 4000 (in
the Core i7-3770K) in our testing with currently popular 3D titles, but
we definitely saw some.
7. ...but still not good enough for intense gaming.
But the fact remains that, despite these changes, you'll still want a
discrete video card if you're serious about playing 3D games like Max
Payne 3, Batman: Arkham City, or The Elder Scrolls V: Skyrim. Neither
generation of Intel HD Graphics was designed to provide outstanding
frame rates in those kinds of titles, particularly with maxed-out
graphical details or at larger resolutions, so a standalone card from
either AMD or Nvidia will enhance your experience tremendously. Don't
care at all about those types of games? Then any incarnation of Intel HD
Graphics will suit you just fine.
8. Ivy Bridge and Sandy Bridge are backward-compatible.
Intel has a not-entirely-undeserved reputation of forcing people to buy
new motherboards every year or every other year if they want to be able
to use the highest-performance CPUs available. The good news is that
that's not the case with Ivy Bridge. Sandy Bridge processors will work
in Ivy Bridge motherboards, and vice versa (although, in that case, you
may need to update your motherboard's BIOS to ensure compatibility). You
may find yourself a little constrained in some ways by using a newer
CPU in an older board, but this is a good way to get your hands on the
latest technologies without having to perform a full-scale upgrade on
your PC. It's also a good way to reduce confusion in the market—and one
we'd be happy to see Intel adopt again in the future.