Techspection: ASUS gives you extra cores for free; but are there downsides?
AMD have stuck with their Phenom architecture for a few years now, a special design when compared to previous chips. It's a monolithic die that includes all four cores as one single immovable chunk, and while this gives the benefit of tightly integrated caches, it has caused problems with AMD's yields to the point where they've had to create a novel - and effective - way of selling most of the chips they manufacture.
The answer, as we first saw in mid 2008, was to take the monolithic quadcore Phenom dies with imperfections, determine which areas of the chip were faulty, and deactivate them. With the faulty core (and later, up to three cores) deactivated, the remaining cores could be sold as a triple- or dual-cored processor, albeit at a lower retail price owing to reduced performance.
However, unlike the difference between Intel's dual and quad chips, these deactivated cores were not physically removed at all. Even more astoundingly, the demand for AMD's dual and triple core chips were so high that their manufacturing process didn't produce enough errors to meet it, and they artificially created 'faulty' chips with extra missing cores.
The enthusiast community isn't one to stand idly by with knowledge like that, and in February of 2009 we saw that the Phenom II X3 chips could be unlocked to create an effective X4 when running in the 790GX chipset. Well, that ability is returning with the 890GX chipset, and ASUS have placed themselves at the forefront of processor unlocking with their M4A89TDG PRO board - which comes with a feature called 'Core Unlocker'.
We grabbed an AMD Phenom X2 550 chip, which is a dual-core processor that runs at a stock speed of 3.1GHz, and threw it into the mobo alongside 4GB of G.Skill RAM at 1600MHz with 8-8-8-24 timings. The Core Unlocker is activated with a simple hardware switch, manually changing BIOS settings and by hitting the '4' key during POST. If all went as planned (and each of the three methods worked just fine for us), the board will POST in a similar way to usual, with the addition of this handy message:
But however confident the BIOS appears to be, did this really give us two completely functioning cores?
Issue: 137 | June, 2012