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Hidden Cores On Phenom CPUs Can Be Unlocked
An anonymous reader writes "One of the major ways a semiconductor manufacturer manages to make the most of its chips is through binning. Chips able to cope with high clock speeds with all cores running end up as premium product lines, while others end up as models rated at lower speed grades, or with fewer cores. In the case of AMD's Phenom CPUs, dual and triple core models are quad cores with some disabled, while some newer quad core CPUs are actually six core models with two disabled. To this end both ASUS and MSI have announced that they have modified versions of AMD 890FX- and 890GX-based motherboards to unlock these hidden cores. Much like overclocking, there is no guarantee that you will gain anything by unlocking the hidden cores — everything depends on just why your CPU ended up in a certain product line."
Unlocking cores that the manufacturer deems to be flawed - um, yeah.
Unless this is a rehash of when Intel were (alleged?) to be selling 486DX processors as 486SX with perfectly good maths co-processor cores disabled, I think I like my data unscrambled! /Lawn etc.
AT&ROFLMAO
I would have gotten first post here, but AMD disabled two of my CPU's cores :/
Now all they need to do is stop selling the processors with all cores guaranteed to work and watch sales skyrocket as people buy half a dozen dual-cores in the hopes of getting one that wasn't damaged. And whoever buys the most CPU's every day gets a working one for free...
I don't know about you, but I would not want to be willingly running a system with a known-bad CPU core
You underestimate the combination of paranoia and lack of sense that a lot of overclockers have, who are convinced the CPU manufacturers intentionally disable their chips in order to make more money somehow by selling them at a lower price.
I think they use one of those ion Cannons from Empire Strikes Back.
No. They ruin the core's self esteem. They tell it, "You're not good enough to work with the others. Just turn off and sit there and stay out of everybody else's way."
Then one day, a gamer comes by and turns it on. But the core is thinking, I can't do this! This is graphics processing! It's intense! I can't keep up with the other cores!
But the gamer, having faith in the little core, turns him on. And low a behold, the little core can do it, but not without being picked on by the other cores. No! They still tell the little core that he's just not good enough. He can't keep up. But the little core hangs in there to fulfill his duty to the gamer - feeling less than every one else.
One day, the gamer upgrades, and the other cores are scared. They can't keep up. The clock is mad now. He screams, "Come on cores you need to keep up!" The little core comes in and takes up the slack, showing the other cores that he indeed can keep up. The other cores shout, "You did it! You can do it! Come and join our click!"
The little core responds, "No, I'm having lunch with the master clock and by the way, he's promoting me to be your boss. You're my bitches now!"
That's how it happens.
RIP America
July 4, 1776 - September 11, 2001
And you underestimate the profit product differentiation can generate.
If you have $300 to spend and you can choose between two products, one for $100 and one for $500. Which will you choose?
Now if I take that $500 product and turn it into a third product, $300 and slightly tweaked to perform less than the $500 product. Which will you choose?
You and I might take the $100 product and pocket the rest, but many buyers will go for the $300 one. As long as manufacturing costs are low it's more profitable to have a range of prices.
This sig is intentionally left blank
This reminds me of "processor affinity" or "affinity mask", whereby you assign software to a particular processor or core. If you want to setup your software so that only less cpu intensive software (cooler) runs on the questionable core, you can do this in Windows 7, and likely for at least some software in Linux (I'm really not sure here), then yes, in theory, you could do this so only Word runs on core #3.
But please remember the wisdom of Yogi Berra when trying to apply a theory like this: "In theory there is no difference between theory and practice. In practice there is."
In other words, your mileage *will* vary.
Tequila: It's not just for breakfast anymore!
For a while I was selling race car / high performance street car suspension systems.
I had discovered that 90% of the aftermarket shocks being sold as performance upgrades were actually crap. The customer is really not qualified to properly evaluate a shock valving and so it is very difficult for them to differentiate between a proper performance shock and a juiced-up pogo stick.
I started putting shocks on a device called a "shock dyno" (which measures the forces produced by the shock at different shaft speeds) and discovered an absolute parade of horror. Details can be read at http://farnorthracing.com/autocross_secrets6.html
To get the good stuff you needed to be paying upwards of $3000 per corner (so $12000 per car) which is far, far out of the price range of most customers.
So I was building packages based on a brand of shock that was pretty decent and much cheaper. Even though the base design was solid, it still suffered from manufacturing variations. To get around this, I would buy batches and then dyno the lot. Shocks that were close to each other became matched sets, and I'd tweak the adjusters on the shock to ensure each pair was as closely matched as possible. On top of that, I designed some hardware to resolve some other tricky problems typical of the off-the-shelf aftermarket designs, and only used the best bang for the buck components to build them.
When done, I provided a race-quality suspension system, dyno-matched (and it came with the data sheets to prove it) that was very nearly the equal of the $3000/corner systems, for about $500/corner. I say "nearly" the equal because the adjusters on my shocks worked nowhere near as well as the adjusters on the expensive shocks, but in terms of absolute performance, they were effectively identical.
There was almost no markup in these parts; I was hoping to make it up on volume and I knew the customer base was price-sensitive.
These suspensions were INCREDIBLE deals. There was nothing else like it anywhere for anything less than 5 times the price, and unlike all the cheaper stuff, I could prove that it worked. What's more, I could run the cheaper stuff on my dyno and prove that it DIDN'T work; that it was categorically JUNK.
I sold almost none of them, and the universal complaint was "too expensive".
Even when I opened up the books, showed what I was paying for the components, explained why *this* part instead of *that* part, explained every single design decision and proved why it could not be made any cheaper without compromising the functionality, over and over again potential customers would choose to buy non-functional (but shiny) JUNK over functional parts based solely on price.
It was mind-boggling, and eventually I just said to hell with it and found something else to do.
The chip manufacturers are right on the ball here. If I were them, I'd be encouraging the creation of these kinds of motherboards and rather than down-rating the high end parts to make mid/low end, I'd be cherry-picking the best ones for the high end and defaulting the output of my fab runs right to the mid/low end SKUs. In fact, I'd be tempted to DESTROY any chip with a bad core and ensure that all the low-end chips were fully functional - specifically to build a reputation for being "overclocker-friendly".
You can't make money off what you DON'T sell. Believe me, I know.
DG
Want to learn about race cars? Read my Book
If a core is just flat out non-functional then yes, you are right, a system wouldn't boot. However that it works mostly doesn't mean there isn't a problem. There could be a single instruction that has a flaw, so everything is fine unless that instruction gets executed but when that happens you get a crash or worse, data corruption.
If you think Prime95 is an accurate test, you are kidding yourself. Prime95 tests the FPU mainly, and is good for heat testing. It is not a full CPU test. So maybe the FPU works great, but one of the other units doesn't.
So no, you don't know that nothing is broken. You assume nothing is broken. Maybe that's fine, however then no bitching if you get data corruption or the like because there was a problem that you didn't know about.
Many AMD motherboards with 710, 750, or 850 SB (south bridge) support unlocking of cores in BIOS - the feature is called as ACC (advanced clock calibration). In fact, right now I am sitting on an X2 555 trying to decide whether to keep it (and have to spend more on DDR3 as well) or return to store; with the potential to unlock it into an X4 955.
However, from some accounts AMD was trying to convince motherboard mfrs. to stop offering ACC in newer boards; so the fact that its working on 890 SB now is the actual news (if the article is correct). Not really surprising though, now that users are getting spoilt into having easy ways to potentially unlock cores it would've been pretty hard to stop that and make competing mobos more attractive :-)