• Welcome to Overclockers Forums! Join us to reply in threads, receive reduced ads, and to customize your site experience!

Thorton (Athlon FX) will physically have 512 KB of cache

Overclockers is supported by our readers. When you click a link to make a purchase, we may earn a commission. Learn More.

c627627

c(n*199780) Senior Member
Joined
Feb 18, 2002
Story so far:

Athlon FX a.k.a.Thorton, unlike T-Bred, will have "Barton grade processor modules without extra L2 cache."

Graphic67's comments about there physically not being extra cache on the Thorton were pointed out to Adrian Wong, the guy who broke the news that Thorton's going to be called Athlon FX:

I asked him if he still stands by his opinion that Thortons will have 512 cache but that half of it will be disabled? He said yes:
http://forums.rojakpot.com/viewtopic.php?p=32063#32063

"Hello c627627,

A popular misconception of microprocessor manufacturing is that it is always cheaper to create a new line for different variants of the same processor, in order to squeeze in more chips per platter. Well, that's true, to some extent.

However, the bulk of the cost of manufacturing a processor does not come from the wafer. The bulk of the cost comes from the machinery used to make the processors and the cost of running them! The wafer is chicken feed by comparison. That's something many fail to take into account.

The cost of running a fab and the machinery is so high than the cost of manufacturing a Barton and a Thoroughbred is really not that much different. The Barton die is larger so it will be a little more expensive but not as much as people perceive.

Look at what you are paying for processors. Do you think it costs AMD more to make 2GHz Athlon XPs compared to 1.7GHz Athlon XPs? No... Cause it's really the same chip! The value of microprocessor is always about perception, never about the actual cost of the chip.

The same reason is why it makes more sense for AMD to make one single type of die (the Barton die) and use them to produce TWO different kinds of processors - the Barton and the Thorton. Because they are essentially the same processor, this gives AMD a lot of flexibility.

They don't have to worry so much about reserving capacity at their fabs. They can just churn out all the Bartons they want! And then they can package the Barton dies as Barton processors or Thorton processors according to the market forces.

Again, the cost of making a processor is NOT as expensive as you might expect. The bulk of the cost is in building and running the fabs. In short, the first chip costs millions to make. The rest are essentially free.

Now, regarding cache failures... Let's not forget the cache is ON-DIE. It's not a separate cache chip or die that is integrated within the processor package. Cache takes up a lot of space. That's why the Barton die is bigger than the Thoroughbred's die.

When a die is bigger, the yield naturally drops even though the defect density for the fab remains constant. The yield drops because of the larger die size. The larger the die, the more likely it is for contaminants to damage it. And due to its size, the Barton's large on-die cache is more susceptible to getting damaged by such contaminants.

As a new core with a larger die, the Barton will naturally have a lower yield than the Thoroughbred. Many of these will be due to damage to the L2 cache. So, what would be the logical thing for AMD to do?

Throw away the chips?

Nah... They are smarter than that. All they need to do is disable half the L2 cache (naturally the defective half!) and they will have a bunch of working processors! Of course, this doesn't mean they can get all their defective chips running. But it does allow them to recover a large portion of their "defective" chips.

And don't forget... Selling microprocessors is always about selling perception. If the market requires more Thortons, AMD is not going to say, "Sorry, we don't have any more defective Bartons to turn into Thortons." They will just disable half the cache of good dies to make them into Thortons.

If you think that's a waste of money, well, that's because you perceive the cost of the processor to be extraordinarily high just because it's a working Barton core. Well, no. It's all about marketing and perception.

If AMD gets to sell you one of their new cores as a Barton (at a higher cost), it would make them very happy. But they are just as happy to sell you a Thorton using the same core (or a defective one) at a lower profit to them. At the end of the day, profit is profit.

Hope that helps you some!
"


How about that mod now to enable the extra 256 KB of cache that's supposedly there?!
 
The cache is most likely burned off and/or broken, just like with the vast majority of 9500np cards that fail to mod to 9700np cards since some of the extra 4 pipelines are broken.
 
Damian said:
The cache is most likely burned off and/or broken, just like with the vast majority of 9500np cards that fail to mod to 9700np cards since some of the extra 4 pipelines are broken.

Video cards != Processors.

Methinks AMD will do something to prevent the full cache from being enabled, but it might just be a matter of shorting some bridges on the cpu to make it work
 
Yes! AMD takes away the Tbred B and gives us a shiny new (cheap) moddable chip!

Its only a matter of time before someone figures out how to do it - AMD aren't like Intel with their evil multiplier locks - they will surely give us a bridge ;)
 
I agree with L337 M33P. They might even have code on the chip that will tell us if they disabled cache that was good or if they diabled damaged cache. That would let us know if it's OK to enable the rest of the cache
 
You gotta love speculation about a chip that hasnt been released yet. Don't get your hopes up too high. :)
 
One thing I wonder about the Thorton's that I haven't seen brought up... will the disabled cache still use energy and produce heat? If not will that extra non heat producing surface area make these chips run a bit cooler than a T-bred? (All things being equal of course.)
 
You guys definitely have your hopes way too high. I'd really really doubt if AMD just decided to stick a bridge right on to the pcb just calling to you to mod it. My guess is that Thortons will be unmoddable altogether. But it is too early for speculation.
 
AMD != Intel for their manufacturing exploits.

With the multiplier problem faced by both AMD and Intel, Intel decided to hard code their chips' multipliers, AMD went the way of the bridges. I think they will follow suit for Thornton
 
why on earth whould they have the cache in there and then burn it or cut it? the main purpose was to save money, and theyd end up spending more money!!
 
And don't forget... Selling microprocessors is always about selling perception. If the market requires more Thortons, AMD is not going to say, "Sorry, we don't have any more defective Bartons to turn into Thortons." They will just disable half the cache of good dies to make them into Thortons.

If you think that's a waste of money, well, that's because you perceive the cost of the processor to be extraordinarily high just because it's a working Barton core. Well, no. It's all about marketing and perception.
 
I wish the home builders do the same. Just building all houses with 4000 sq ft, and many demands are for 2000 sq ft houses. So when I buy a house of 2000 sq ft, they give me a 4000 sq ft house with half of the area diabled, possibly with only locked doors.

So afterwards, I can try to unlock those area by some kinds of mods.
 
I';m looking forward to this thorton but not becaue I want to mod it to get extra cache. with a larger surface area these chips should be easier to cool thatn the tbred b's my guess is 2.6 will be reachable on air with a good stepping of these chips.
 
Snvpa: If it is the same core process that the Barton's use, I seriously douvt that 2.6 will be attainable on air. You are assuming that they are doing something different to the core: difference between the t'bred A and the t'bred B is an extra layer hence the better overclockability. The bartons at their best are hitting 2.3Ghz - 2.4Ghz on air cooling despite the extra cooling area.
 
I think that the newest Bartons have potential for a lot more. One person on these forums bought a 3200+ and got it to 2.5 on stock voltage; its nothing like the 2500+'s we usually see. Most of us don't have the dough to see procs overclocking that high and that easily, but if we did, 2.6ghz on air might be a little more common. When wafers of that purity trickle down to the Thortons, I wouldn't rule out 2.6ghz on air as being reasonable.
 
hitechjb1 said:
I wish the home builders do the same. Just building all houses with 4000 sq ft, and many demands are for 2000 sq ft houses. So when I buy a house of 2000 sq ft, they give me a 4000 sq ft house with half of the area diabled, possibly with only locked doors.

So afterwards, I can try to unlock those area by some kinds of mods.

Unfortunately those mods would entail the risk of your house burning down...:mad:
 
hitechjb1 said:
I wish the home builders do the same. Just building all houses with 4000 sq ft, and many demands are for 2000 sq ft houses. So when I buy a house of 2000 sq ft, they give me a 4000 sq ft house with half of the area diabled, possibly with only locked doors.

So afterwards, I can try to unlock those area by some kinds of mods.

that would be awsome!!!!! to get twice the house :D

or to unlock the other half of the cache :D

but why not just make thornton a low model and a high model. the low wold be the one with the disabled cache and the high one being a barton.
 
Back