Intel Core i7-3770K review

Intel’s new Ivy Bridge processors are finally here. You may have hear of Intel’s Tick-Tock strategy, where a Tick is a new, smaller production process and Tock is a major architecture change, and the Ivy Bridge range is officially a Tick – it has a new 22nm process, compared to Sandy Bridge’s 32nm, but its core processor architecture hasn’t changed. However, the new processors do have a significantly improved graphics architecture, which promises more speed in games as well as faster GPU-assisted video encoding with Intel’s QuickSync technology. Because of this Intel is describing Ivy Bridge as a ‘Tick+’.

Compared to Sandy Bridge, the new processors have a smaller 22nm process for lower power consumption and a smaller TDP

COMPATIBILITY

Intel has kept the same Core i5 and Core i7 branding – but with Ivy Bridge labelled as “3rd Generation Intel Core” – which could be confusing. Far more perplexing, though, are the compatibility issues. The good news is that Ivy Bridge uses the same LGA1155 socket as the previous generation. There is a new range of 7-series motherboard chipsets designed to be used with the new processors (Z77, Z75 and H77), but the processors will also work on the H61, H67, P67 and Z68 motherboards – with one caveat.

The older chipsets will need to be updated to support Intel’s new ME8 Management Engine, which is apparently more complicated than a simple BIOS update and will need to be done by the manufacturer. Intel recommends you get confirmation from the manufacturer that a motherboard will support Ivy Bridge before you buy, or just get a board with a 7-series chipset.

The die shrink means the processors will run cooler – they have a 77W TDP, down from Sandy Bridge’s 95W. This lower heat output means the chips can Turbo Boost for longer, which should lead to better performance in desktop tasks than on Sandy Bridge, despite the same core architecture. This theory was borne out by our test chip’s performance in our 2D application benchmarks. Intel sent us the Core i7-3770K to test, which is a 3.5GHz quad-core chip with Hyper-Threading, so appears as eight processors in Windows. The processor can Turbo Boost up to 3.9GHz for added performance, but for how long depends on how cool it is kept.

Graphics hardware now takes up a larger proportion of the chip’s surface

To see how much application performance had improved, we compared the Ivy Bridge processor to a previous-generation Sandy Bridge chip. The processor’s Sandy Bridge equivalent is the Core i7-2700K, which also runs at 3.5GHz with a Turbo Boost up to 3.9GHz. We only had an Intel Core i7-2600K available for testing, which runs at 3.4GHz with a 3.8GHz Turbo Boost, so we raised its Turbo Boost headroom to 3.9GHz to make it largely equivalent – this is only a 2.5% overclock.

APPLICATION BENCHMARKS

The Ivy Bridge processor was much faster in our benchmarks – which are normalised to a Core i5-2500K scoring 100. In our video-encoding test we saw a score of 154 from the i7-3770K, compared to 103 from the i7-2600K. In our multitasking test, the Ivy Bridge chip managed 126, while we saw 114 from the Sandy Bridge model. This led to overall scores of 132 from the i7-3770K, compared to 112 from the overclocked i7-2600K – the new chip is around 15% faster in our benchmarks.

This seems to be because the chip’s lower heat output means it can maintain a Turbo Boost speed for longer; we kept an eye on CPU-Z’s processor speed monitor during our benchmarks, and found that the Ivy Bridge processor stayed at maximum Turbo Boost for the entire benchmark suite, while the Sandy Bridge processor had to throttle back to its normal speed a quarter of the way through. In both cases we only used Intel’s stock cooler. Even when we disabled all but one core on both processors, the Ivy Bridge chip managed 35 overall compared to 30 from the Sandy Bridge processor, showing the new chip to be around 15% faster core for core in real-world tasks.

OVERCLOCKING AND REAL WORLD TESTS

The new chip also overclocks well. We raised the Turbo Boost ceiling from 3.9GHz to 4.3GHz on both processors to make a 10% overclock. Once again, even using the small stock Intel cooler, the processor managed to get all the way through our benchmarks without throttling back from its maximum Turbo Boost speed. This led to a huge overall score of 137, compared to 122 from the Sandy Bridge processor, which, again, had to throttle back a quarter of the way through.

To test the improved QuickSync, we used Cyberlink’s MediaEspresso 6.5 video conversion software. With QuickSync disabled and using the Sandy Bridge Core i7-2600K processor, set to a 3.9GHz Turbo Boost, we converted a six-minute 1080p AVCHD video file to iPhone 4 H.264 format in 4m 18s. With the Ivy Bridge Core i7-3770K processor the same test finished in 4m 7s. Once we enabled QuickSync we saw 2m 1s from the Sandy Bridge processor and just 1m 35s from the Ivy Bridge processor – meaning you should be able to encode a two-hour AVCHD file to play on your phone in around 30 minutes.

With QuickSync disabled, the new Ivy Bridge chip has a slight advantage over Sandy Bridge

With QuickSync enabled, the new chip flies ahead

GRAPHICS BENCHMARKING

Finally, we saw how Intel’s new HD Graphics 4000 chipset compared to the HD Graphics 3000 in the previous-generation processor. In Dirt 3, running at 1,280×720 with High detail and 4x anti-aliasing, we saw 26.1fps – an improvement on the i7-2600K’s 21.6fps, but not smooth enough to be playable. However, without anti-aliasing we saw 39.6fps, compared to the just-playable 30.1fps from the Sandy Bridge chip, so if you’re willing to put up with console-quality graphics some gaming is on the cards. The new chips are still far slower in games than AMD’s last-generation Llano processors, and AMD has yet to launch its 2012 range of chips, which should be even faster in 3D.

Dirt 3 isn’t the most challenging of titles, but it’s representative of current games aimed at today’s home consoles

CONCLUSION

Intel has pulled off another blinder with Ivy Bridge. The new graphics are a fair improvement, making playing games at reasonable detail levels finally a possibility, but the real surprises come in 2D applications. The smaller process means the new chip can run at its maximum Turbo Boost almost all the time, which makes it far quicker in intensive tasks than its Sandy Bridge predecessors. The high-end i7-3770K is a hugely fast processor, so wins an Ultimate award; but unless you need the best, you should wait to see how cheaper, upcoming chips in the range perform, as they may be better value.

You can read our first Ivy Bridge PC review now, as we test an overclocked Intel Core i5-3570K in the Palicomp Alpha Detonator.