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Technology Stocks : Advanced Micro Devices - Moderated (AMD) -- Ignore unavailable to you. Want to Upgrade?

To: Mani1 who wrote (51712)	8/20/2001 2:56:59 AM
From: wanna_bmw	Read Replies (1) \| Respond to of 275872

Mani, thanks for the detailed post. I really appreciate it when someone explains their reasoning such as you have. I do have one question, though. If Intel's heat spreader does such a good job at reducing the thermal liability, doesn't that cancel out the disadvantage of the actual die having a lower tolerance, thus making the argument moot? Besides, isn't the normal temperature for a properly cooled system at the point of contact well below either rated maximum? wanna_bmw

To: Mani1 who wrote (51712)	8/20/2001 4:40:01 AM
From: Yousef	Read Replies (3) \| Respond to of 275872

Mani, Re: "AMD's die can simply handle a lot higher temperature than Intel can. Why? I don't know." It appears reading through all of this, that I have drawn the conclusion that Intel rates their chip to operate at a different die/junction temperature (~80C for INTC versus 95C for AMD) ... Is this correct, Mani?? If true, this would indicate a different level of required chip reliability between the two companies. Make It So, Yousef

To: Mani1 who wrote (51712)	8/20/2001 10:52:50 AM
From: heatsinker2	Read Replies (1) \| Respond to of 275872

Mani- AMD's die can simply handle a lot higher temperature than Intel can. Why? I don't know. Nice technical details. I am saving this post for future reference. Now why is Intel Tjmax less than the AMD Tjmax? I can come up with these possible reasons: 1. Intel designs with a greater margin of safety. For example, Intc may be targeting a lifetime of 10 years while AMD thinks 8 years is acceptable. It has to be said that microprocessors usually last a pretty long time (the PC becomes hopelessly outdated before the chip dies), so a lower design lifetime could be acceptable. 2. Due to ignorance, AMD is using a lower margin of safety. It is ENTIRELY possible that AMD is not as good as Intel in reliability matters. They think that Athlons will live as long as a p3, but they won't. 3. Intel uses lower cost packages which can't handle the temperature cycles. To oversimplify a bit, semiconductors die due to either elevated operating temperatures (lifetime reduced by a factor of 2 for each 10C increase in Tj) or temperature cycling (mechanical stresses related to thermal expansion). AMD has been using ceramic packages which have better thermal cycling performance because of a better match of expansion coefficient between silicon and the package materials. So I vote for #3, althought I don't completely rule out #2 (ignorance is bliss). With crazy Jerry at the helm, #1 is also a possibility.