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The samples have circulated. The benchmarks are in. Hell, there’s even been a sweaty, subtitled Hitler rant courtesy of the time-honoured Downfall YouTube meme. That’s right folks, AMD’s all-new Bulldozer CPU is finally here. And it’s absolutely, positively awful.

To understand just how bad it really is, turn your attention to a single, frankly rather arbitrary statistic. I speak of Bulldozer’s two billion transistor count. That’s right, AMD’s all new CPU is a monster the likes of which desktop processing has never previously known. To put that figure into context, consider the number of transistors contained in several existing CPUs. Intel’s popular four-core Sandy Bridge chips, for instance, have under a billion despite the minor matter of a powerful integrated graphics processor.

AMD’s four-core Phenom IIs clock in at 758 million, while the six-core AMD Thuban chip tips the scales at 904 million. Even Intel’s mighty six-core Gulftown machine only soaks up 1.17 billion of the little binary blighters.

Bulldozer, then, has nearly twice as many transistors as any previous CPU. It is by far and away the most complex PC processor ever, which raises the question of how on Earth AMD contrived to make it such a mediocre performer. By most metrics, you see, Bulldozer struggles to beat Intel’s Core i5 2500K.

Lest we forget, the 2,500K is not just a middling to low-end quad-core processor by Intel’s standards. It’s actually a chip that has been intentionally hobbled courtesy of locking out Intel’s HyperThreading feature. Drill down into the details of Bulldozer’s performance and the picture just gets uglier and uglier.

One of the most shocking factoids involves a comparison with AMD’s existing Phenom II architecture. Running single threaded code at 3.6GHz, a Bulldozer core produces less performance than a Phenom II core at 3.3GHz. I’m not sure how that’s even possible, but clearly something has gone horribly, horribly wrong with AMD’s plans for Bulldozer. As for the single-threaded comparison with Intel processors, the match up is absolutely hideous. Intel’s cores are fully 50 per cent faster, despite slower clockspeeds.

You could say it’s no surprise that Bulldozer is a bit slower core-for-core than even AMD’s own incumbent architecture. After all, this is a radical new design in which a pair of integer units sharing a single floating point execution resource count as two cores. But then you remember that you could match Bulldozer’s notional eight cores by doubling the number of cores in a Sandy Bridge quad-core processor and still come out well under Bulldozer’s two billion transistor count.

So, Bulldozer’s so-called modules may have shared resources, but you could hardly call its cores cut down. They’re huge. Making matters worse, Bulldozer isn’t even that hot at multi-threading: the discipline that the innovative modular architecture was supposed to rule. AMD sneers that Intel’s HyperThreading is a hack and Bulldozer offers a more robust multi-threading power plant, but more often than not, four HyperThreaded Intel cores beat eight Bulldozer cores, plain and simple.

The most depressing realisation is that AMD could have produced a smaller, faster chip by simply chucking another couple of cores onto its six-core Thuban processor. It would then have a bona fide eight-core chip that would beat Bulldozer for single and multi-threaded workloads, would cost a fraction of the amount to engineer and would be far cheaper to make.

If all that wasn’t bad enough, it turns out Bulldozer is a real power hog, too. It’s by far the least energy efficient performance CPU under load. On the desktop I can’t say I’m terribly bothered how much power a CPU sucks up, but heavy consumption is a classic indicator of a troubled architecture and it bodes very badly indeed for Bulldozer as the basis of a laptop processor.

All of which will have you wondering why AMD bothered with Bulldozer. Well, its existing CPU architecture dates back to 2003 and it was slipping ever further behind Intel. Clearly something radical was needed, but equally clearly, Bulldozer is not it.

Make no mistake, this is bad news for you and me. Already, Intel is taking liberties thanks to a lack of competition from AMD. The feeble debut of Bulldozer will only make Intel bolder. Moreover, given how long it’s taken AMD to get Bulldozer out the door, it’s hard to imagine things improving for a very long time. Just as well that’s today’s chips are pretty quick. Because odds are we’ve several years of stagnation ahead.