Rumour: Bulldozer 50% Faster than Core i7 and Phenom II.

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IntelUser2000

Elite Member
Oct 14, 2003
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Now don't laugh at me. But my guess on clock speeds is.

3.3ghz for the X110 models. And 3.5ghz for the single 8130p model.

That actually sounds alright for a base clock. TurboCore can add to that.

Drizek: It probably means there will be cache-disabled versions. There might be a 8xxx with 8MB and 6MB L3 for example.
 

drizek

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Jul 7, 2005
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I don't remember seeing anything about the L3 cache of the 4 core version, but if it has "up to" 8MB then does that mean that a standard one has 4MB and the 8MB models will be gimped 8-cores with 2 modules disabled but all the cache intact?
 

IntelUser2000

Elite Member
Oct 14, 2003
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I don't remember seeing anything about the L3 cache of the 4 core version, but if it has "up to" 8MB then does that mean that a standard one has 4MB and the 8MB models will be gimped 8-cores with 2 modules disabled but all the cache intact?

That sounds about right.
 

Ajay

Lifer
Jan 8, 2001
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So I was basically right about the prices. They are positioning them to compete with the 2x00Ks.

$130 for a quad core, $350 for a high end octalcore. <$230 for the hexcore, <$300 for at least one octalcore. That's my guess anyway.

Not according to the Xbitlabs posting right above yours. High end Octa-core will be $700+.
 

Phynaz

Lifer
Mar 13, 2006
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AMD doesn't need BD to have higher IPC than SB. As long as BD can clock high enough to be "close" to SB's singlethreaded performance, and beats SB in multithreaded performance, it will be fine.

Netburst comes to mind.
 

podspi

Golden Member
Jan 11, 2011
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Netburst comes to mind.


Don't forget they expected clock speeds to hit ~ 10ghz. Assuming AMD hasn't deluded itself into unreasonable clock speed expectations, and knowing (from JFAMD) that IPC increases, I think it is possible for BD to have lower IPC than SB and still be competitive in singlethreaded applications. For multithreaded applications throughput will win over singlethread, and clockspeed will not be as important.
 

gdansk

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Feb 8, 2011
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I was just reading Anand's Nehalem review and he mentioned that Intel switched from domino transistors to static CMOS. Does anyone know if this has been done by AMD as well? I believe AMD said Bulldozer was designed inherently for high clocks, so perhaps, it will continue using domino transistors which should help increase maximum clock rate. Any information on this?
 

Idontcare

Elite Member
Oct 10, 1999
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I was just reading Anand's Nehalem review and he mentioned that Intel switched from domino transistors to static CMOS. Does anyone know if this has been done by AMD as well? I believe AMD said Bulldozer was designed inherently for high clocks, so perhaps, it will continue using domino transistors which should help increase maximum clock rate. Any information on this?

You need your PMOS drive currents to be comparable to your NMOS drive currents in order for the switch from domino to static cmos logic to make sense.

This switch was enabled by Intel's gate-last integration because the strain-engineering that comes with gate last results in a PMOS drive current that is very large and on par with NMOS.

GloFo insisting on gate-first for 32nm HK/MG integration means their PMOS drive currents don't benefit from the same stain engineering opportunities, so no outsized PMOS drive current bumps, so no PMOS to NMOS drive current parity, so no enabling benefits of converting to static cmos.

Gate-first is great for high density, meaning lower production cost per die produced. Gate-last is great for high performance, your drive currents will be higher which means higher ASP for your products when selling in a performance sensitive market.
 

CTho9305

Elite Member
Jul 26, 2000
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You need your PMOS drive currents to be comparable to your NMOS drive currents in order for the switch from domino to static cmos logic to make sense.

This switch was enabled by Intel's gate-last integration because the strain-engineering that comes with gate last results in a PMOS drive current that is very large and on par with NMOS.

GloFo insisting on gate-first for 32nm HK/MG integration means their PMOS drive currents don't benefit from the same stain engineering opportunities, so no outsized PMOS drive current bumps, so no PMOS to NMOS drive current parity, so no enabling benefits of converting to static cmos.

Gate-first is great for high density, meaning lower production cost per die produced. Gate-last is great for high performance, your drive currents will be higher which means higher ASP for your products when selling in a performance sensitive market.

I suspect a simpler answer: device variation. If you consider a dynamic wide-NOR with a keeper (let's say 16 parallel pulldowns for a 16-input NOR), it only works so long as the weakest nmos pulldown is stronger than the pmos keeper, and the leakage of all the nmos pulldowns combined is weaker than the pmos keeper. These requirements are conflicting - in one case you want stronger Ns, and in the other you want stronger Ps, so there's a window of functionality that's bounded at both ends.

If you have a lot of variation, you can find yourself in a situation where no size ratios can guarantee both conditions (i.e. sometimes your pmos will be a little too weak and your nmos a little too leaky, or sometimes your pmos will be a little too strong and your nmos a little too weak). Variation has been getting worse with each new process node. Also, some variation effects tend to be exacerbated at lower voltages too, and with the modern push for low power, you may make tradeoffs to support a lower Vmin. Intel may have gone static because dynamic was too risky (or too big/slow once you increase sizes enough that you can tolerate the device variation). Static CMOS logic works pretty well so long as your transistors look kinda sorta transistor-like. Dynamic logic's advantage has been shrinking for a long time.

They may also have gone static to simplify porting to 32nm/22nm, or because they want to use more automated synthesis and place&route, which generally work best with static logic gates (ignoring Intrinsity's Fast14 stuff). As I think about this more, there are a whole bunch of other possibilities too... but that's good enough for this post.

If there are parts of this post you (or anyone) don't understand, I can attempt to clarify or draw pictures.
 

AtenRa

Lifer
Feb 2, 2009
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ASUS pledges support for AM3+ both for current and future motherboards

92aq.jpg
 

TuxDave

Lifer
Oct 8, 2002
10,571
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You need your PMOS drive currents to be comparable to your NMOS drive currents in order for the switch from domino to static cmos logic to make sense.

This switch was enabled by Intel's gate-last integration because the strain-engineering that comes with gate last results in a PMOS drive current that is very large and on par with NMOS.

GloFo insisting on gate-first for 32nm HK/MG integration means their PMOS drive currents don't benefit from the same stain engineering opportunities, so no outsized PMOS drive current bumps, so no PMOS to NMOS drive current parity, so no enabling benefits of converting to static cmos.

Gate-first is great for high density, meaning lower production cost per die produced. Gate-last is great for high performance, your drive currents will be higher which means higher ASP for your products when selling in a performance sensitive market.

Unfortunately I wasn't around early enough to hear how the decision making went down but was only around to hear the final bullet points on why lots of things went static. Simply put after getting burned with exotic domino logic in Prescott they wanted something lower power and something that has better correlation to simulations. As far as I know, those were the only two points made to me describing the design methodology. The whole tradeoff of design methodology based on beta could've been involved but I just wasn't around to hear it.

There's still domino where it's useful but we don't need domino for our adders anymore. Static is stupidly fast on the process.
 

podspi

Golden Member
Jan 11, 2011
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AMD is not supporting BD in AM3 sockets. Period.

It might be a good idea for AMD to talk to ASUS, and either tell them to fix this, or (if it is true, which you said it isn't) confirm it.



Confusion like this is bad.
 

drizek

Golden Member
Jul 7, 2005
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Just because AMD doesn't support it doesn't mean that Asus can't hack it.

Either it is:

1. Supported by Asus but not AMD
2. Asus is using an AM3+ socket
 

Idontcare

Elite Member
Oct 10, 1999
21,110
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Just because AMD doesn't support it doesn't mean that Asus can't hack it.

So true. AMD didn't exactly support the GFD (gold-finger-device) for overclocking SlotA athlons but it sure the heck worked rather well (I owned several GFD's).
 
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