Intel Core i5-750

The Core i5-750 is one of Intel’s first three CPUs based on the Lynnfield core (the other two being the Core i7-860 and the Core i7-870). It’s a refinement of the Nehalem microarchitecture first revealed in the Core i7-900 series CPUs.

Like its stablemates, the i5-750 combines four CPU cores on one 45nm die, with on-chip memory and PCI bus controllers. The 8MB of shared L3 cache remains too. And rather than the LGA 1366 format of the older Core i7s, Lynnfield chips use the more petite new LGA 1156 socket.

The most exciting development is Turbo Mode, which borrows power from idle CPU cores to overclock active threads. This was introduced with the first Core i7 CPUs, but those parts could boost a single thread only by a maximum of 266MHz, whereas Lynnfield can raise the speed of a single core by as much as 667MHz – a significant enhancement.

Though Core i7 parts feature Intel’s Hyper-Threading technology, the Core i5 operates as a straightforward quad-core processor. And its clock speed is lower than any i7: disregarding Turbo Mode, it runs at a nominal speed of 2.66GHz, compared to 2.8GHz for the Core i7-860 and 2.93GHz for the Core i7-870.

Performance

Yet in real life the Core i5-750 performs very well. When tested in a Gigabyte P55 motherboard with 2GB of DDR3-1066 RAM, an ATI Radeon HD 4550 graphics card and a Seagate Barracuda 7200.12 hard disk, it powered the system to a persuasive 1.85 in our real world benchmarks. That places it effectively neck and neck with the older Core i7-920, which scored 1.86 in a similar configuration.

What’s more, Lynnfield CPUs consume far less power than their predecessors. Thermal design power for the Core i5-750 is quoted as 95W, but our test system idled at a stunningly low 60W, and even when we drove all four cores up to full load, total power draw peaked at just 124W. Some older Core i7 systems draw that much when idle.

Price

The best part is that the Core i5-750 is unexpectedly affordable, with early pricing coming in as low as £142 exc VAT. If that holds up it would make it a very attractive alternative to a Core i7-920 — especially since P55 motherboards are also significantly cheaper than X58 models.

The obvious alternative is AMD’s Phenom II X4 965, which can deliver superior performance for a similar price. But if power efficiency is a concern, Lynnfield makes the Phenom looks absurdly Watt-hungry.

It’s clear that, once again, Intel has raised the technological bar, and we suspect the Core i5-750 will be a hit with system builders and enthusiasts alike.

Author: Darien Graham-Smith