Sandy Bridge, Part 1: Intel GMA HD 3000/2000 Graphics

CPUs|Motherboards
Viewing page 1 of 7 pages. 1 2 3 4 5 6 7 Next
Sandy Bridge Pt.1: Intel GMA HD 3000/2000 Graphics [Updated: 05 January]

January 2, 2011 by Lawrence Lee

POSTSCRIPT 2: GMA HD 2000 Test Results
05 January 2011 - see page 7

In the Fall of 2008, Intel launched the Nehalem processor architecture, the first major change to their chip designs in a couple of years. Both the CPUs and motherboards for the new LGA1366 socket were (and still are) relatively expensive, so only power users and enthusiasts were willing to plunk down the cash for the new hardware. A year later, they released more cost-effective processors on a new socket, LGA1156. Like most budget CPUs, they were cut down, this time with lower clock speeds, a slower interface, and a dual channel memory controller instead of triple. They also split up some of the functions of the northbridge chip (eliminating it), putting some on the processor and bundling the rest with the southbridge in a new chip called the PCH. This made the platform more energy efficient, enabling broad appeal for both home and enterprise markets.

In Q1 of 2009, LGA1156 finally got dual core processors manufactured using the new 32nm fabrication process and an integrated graphics chip (albeit a 45nm one) placed on the same package to further improve efficiency. Dubbed Intel GMA HD, this GPU turned out to be just about perfect for decoding high definition content. Its 3D performance was significantly faster than its predecessors, although it still didn't have enough mustard to take on AMD's best IGP.

The next salvo from Intel takes place today, the release of yet another processor microarchitecture, dubbed Sandy Bridge. As you can imagine, a large scale tech product launch is both nerve-wracking and arduous for the company involved, their partners, the retailers, and the press covering it. While most of our readers are end-users who reap personal benefit from new products, they too are equally afflicted. As the NDAs lift, the web explodes with information from dozens of publications, each with their own take on the latest and greatest. Then the masses get to pore over this mountain of data to form their own opinions, before deciding whether to rush out and buy these new gizmos. (Editor's Note: That Intel set the embargo lift date for Sandy Bridge to Jan 2 deserves long rants by/for tech journalists. Has Intel not heard that Christmas to New Year is a huge holiday break for most of the western world?)

It's an especially daunting task for a launch like this one, as there are new sockets, chipsets, and motherboards as well as the CPU. Rather than throw everything into a single article and overwhelming both you and us, we're going to try to break down Sandy Bridge into its constituent parts and discuss the merits and drawbacks of each over the next week. Obviously there will be some overlap as you can't really discuss one without the other as everything is brand new. Today's topic is Intel's new high-end integrated graphics chip (if you think there can be such a thing), the GMA HD 3000 in the new Sandy Bridge CPUs.

The Chips


A Sandy Bridge processor broken down.

The first thing you need to know about desktop Sandy Bridge chips is they require a new socket, LGA1155 which will eventually replace LGA1156 — even though the latter is barely a year old. Similarly, LGA1366 will be superseded later this year by LGA2011. Assuming LGA775 is still clinging on at that time, Intel will have a ridiculous total of five desktop sockets. So what is different, besides the loss of one pin? Well, for starters the CPU shares its die with an integrated GPU, allowing it to share the L3 cache and providing quick to the integrated memory controller. It all fitted on the same die, even with quad cores, by manufacturing both the GPU and CPU using a 32nm fabrication process. As usual, many minor technical optimizations and improvements have been made, with the end result being an estimated 20~30% performance jump compared to the previous generation.


2nd generation Core i3/i5/i7 lineup.

The new CPUs come in three flavors, following similar conventions with regard to nomenclature. The i7's are fully equipped quad cores with all the amenities, while the i5's lack Hyper-Threading and have 2MB less L3 cache. The i3's are dual core processors with only 3MB of cache and lack TurboBoost, advanced virtualization features, and the AES-NI decryption/encryption instruction set. Power consumption has been kept down, with the quad and dual cores having TDPs of 95W and 65W respectively. Low power 35W/45W/65W models are also on the menu, but we have no information on pricing or availability at launch. The latest missive from Intel tells us that all desktop/mobile SNB SKUs will be launched at CES, and quad cores will be available in the same week. Dual core parts – both desktop and mobile – will ramp in availability 4-6 weeks later. This goes for ULV mobile parts too.

Of particular interest is the "K" variant i5/i7 which trade fewer virtualization features for unlocked multipliers. Without a wide multiplier range, Sandy Bridge CPUs are severely limited in overclocking capability because the base clock frequency cannot be increased much higher than the stock 100 MHz. The "K" models are also the only chips with HD 3000, while the rest get by with the slower HD 2000. Today, we are using i5-2500K for testing, a quad core running at 3.3 GHz, higher clock speed than any quad on LGA1156. With a 1k unit price of US$216 it won't be much more expensive than the Core i5-760 which operates at only 2.8 GHz.

GMA HD 2000 / 3000 Graphics

Like GMA HD, there are two versions of the new Intel HD graphics. They are both clocked the same but; HD 2000 has 6 execution units (similar to shader/stream processors) while HD 3000 has 12. Oddly enough HD 3000 is only available on the "K" series, though the i7's allow for a higher maximum dynamic graphics frequency. The GPU core has a variable speed that works much in the same way as TurboBoost. TurboBoost overclocks the CPU cores depending on how many are in use and what Intel calls Power Sharing overclocks the GPU in a similar fashion. The two chips reside on the same die and the GPU will speed up to the maximum frequency unless the whole package exceeds the designated thermal limit.


New video features.

Along with a bump in clock speed, the new GPUs support the HDMI 1.4 standard with 3D stereoscopic playback, and hardware encoding for H.264 and MPEG-2 video (for applications that support it) and minor image enhancement features. The features-set has also been upgraded to DirectX 10.1 and Shader model 4.1. With all these improvements and changes to the architecture, Intel claims their new GPU is comparable to entry level discrete cards from its competitors.

Chipsets


Chipset comparison.

LGA1155 kicks off with two consumer chipsets, H67 and P67. The only difference is that H67 has support for the integrated graphics and its associated features, while the more expensive P67 has "Performance Tuning" which is code for overclocking. MSRP for Intel's first boards, the DH67BL and DP67BG are US$107 and US$184, respectively, quite a large difference. It seems that purchasing a "K" series processor for a few dollars more is just the beginning. Thrifty enthusiast overclockers are more than justified to feel disappointed.



1 2 3 4 5 6 7 Next

CPUs|Motherboards - Article Index
Help support this site, buy the Intel DH67BL Micro ATX H67 Motherboard from one of our affiliate retailers!