Re: Skeptical about claim that stamp creation burns out modern CPUs
Tim May [EMAIL PROTECTED] wrote: Now I grant you that I haven't tested CPUs in this way in many years. But I am skeptical that recent CPUs are substantially different than past CPUs. I would like to see some actual reports of burned literally CPUs. I've never seen a burned literally CPU, but I have tracked the demise of an AMD K6 (or K6-2, can't remember now) from hot carrier effects. If all processors were made like that one, you would see a lot more load-induced failures. -- Riad Wahby [EMAIL PROTECTED] MIT VI-2 M.Eng
Re: Skeptical about claim that stamp creation burns out modern CPUs
-- On 1 Jan 2004 at 10:44, Tim May wrote: Further, junction-to-case temperature in a ceramic package has a time constant of tens of seconds, meaning, the case temperature reaches something like 98% of its equilibrium value (as wattage reaches, say, 60 watts, or whatever), in tens of seconds. The time constant for the CPU+plus cooling system is a good deal longer, and in modern CPUs the large mass of the cooling system can result in quite long periods, for example a quarter of an hour, before CPU load results in heat related shut off. We also used to run CPUs at 125 C ambient Today's CPUs will generally fail a bit above seventy centigrade. They frequently fail in ways that cause them to draw increased current, eventuallly incinerating the motherboard. To prevent this, always look for the bios option to shut down the motheroboard in the event of CPU overheating. --digsig James A. Donald 6YeGpsZR+nOTh/cGwvITnSR3TdzclVpR0+pr3YYQdkG Uw0lUnQOu8bBc6kOrcDpYZKS0DjzIgrXM9AJSVh2 49rBlWsHg9Teys0ELS5pT26g56P8tEMtp/mQ3eihl
Skeptical about claim that stamp creation burns out modern CPUs
On Jan 1, 2004, at 8:13 AM, Eric S. Johansson wrote: actually, we mean burned literally. the stamp creation process raises the temperature of the CPU. Most systems are not build for full tilt computational load. They do not have the ventilation necessary for reliable operation. So, they may get by with the first 8-12 hours of stamp generation (i.e. roughly 2000-3000 stamps per machine) but the machine reliability after that time will degrade as the heat builds up. Feel free to run this experiment yourself. Take a cheat machine from your local chop shop, run hashcash in an infinite loop, and wait for the smoke detector to go off. there is nothing quite like waking up to the smell of freshly roasted Intel. I'm skeptical of this claim. A lot of Intel and AMD and similar machines are running full-tilt, 24/7. To wit, Beowulf-type clusters, the Macintosh G5 cluster that is now rated third fasted in the world, and so on. None of these machines is reported to be burning up literally. Likewise, a lot of home and corporate users are running background tasks which are at 100% CPU utilization. (Examples abound, from render farms to financial modeling to... Friends of mine run a bunch of 2 and 3 GHz Pentium 4 machines in CPU-bound apps, and they run them 24/7. (Their company, Invest by Agents, analyzes tens of thousands of stocks. They use ordinary Dells and have had no catastrophic burned literally failures.) Further, junction-to-case temperature in a ceramic package has a time constant of tens of seconds, meaning, the case temperature reaches something like 98% of its equilibrium value (as wattage reaches, say, 60 watts, or whatever), in tens of seconds. (For basic material and physics reasons...I used to make many of these measurements when I was at Intel, and nothing in the recent packaging has changed the physics of heat flow much.) We also used to run CPUs at 125 C ambient, under operating conditions, for weeks at a time. Here the junction temperature was upwards of 185 C. Failures occurred in various ways, usually do to electromigration and things like that. Almost never was there any kind of fire. Just burnout, which is a generic name but has nothing of course to do with burning in the chemical sense. Now I grant you that I haven't tested CPUs in this way in many years. But I am skeptical that recent CPUs are substantially different than past CPUs. I would like to see some actual reports of burned literally CPUs. By the way, I have run some apps on my Macintosh 1 GHz CPU which are CPU-bound. No burn ups. I'd like to see some support for the claim that running a stamp creation process is more likely to burn up a modern machine than all of these apps running financial modeling, render farms, and supercomputer clusters are doing. Until then, render me skeptical. --Tim May
Re: Skeptical about claim that stamp creation burns out modern CPUs
On Jan 1, 2004, at 2:35 PM, Eric S. Johansson wrote: Tim May wrote: I'm skeptical of this claim. A lot of Intel and AMD and similar machines are running full-tilt, 24/7. To wit, Beowulf-type clusters, the Macintosh G5 cluster that is now rated third fasted in the world, and so on. None of these machines is reported to be burning up literally. Likewise, a lot of home and corporate users are running background tasks which are at 100% CPU utilization. I will admit to a degree of skepticism myself even though I am describing overheating as a likely outcome. But what is your actual evidence, as opposed to your belief that overheating is a likely outcome? I have said that I know of many machines (tens of thousands of CPUs, and probably many more I don't know about directly) which are running CPU-bound applications 24/7. I have heard of no burning up literally cases with the many Beowulf clusters, supercomputers, and 24/7 home or business screensavers and crunching apps, so I suspect they are not common. If you have actual evidence, as opposed to likely outcome speculations, please present the evidence. First, if you lose a fan on an Intel CPU of at least Pentium III generation or an AMD equivalent, you will lose your CPU to thermal overload. This is a well-known and well-documented problem. One question is can stamp work thermally overload and damage a CPU. Second question is how much stamp work can you do without thermally overloading the CPU. This is true whether one is running Office or a stamp program. You are just repeating a general point about losing a fan, not about stamp generation per se. Boxer fan lifetimes are usually about comparable to hard drive lifetimes, which also kill a particular machine. You are not presenting anything new here, and the association with stamp generation is nonexistent. Large clusters have more careful thermal engineering applied to them than probably most of the zombies out there. I have seen one Beowulf cluster constructed out of standard 1U chassis, motherboards, fans etc. and frequently 10 percent of the systems are down at any one time. The vast majority of the failures have been due to thermal problems. Most clusters use exactly the same air-cooled machines as are available from Dell, Sun, Apple, etc. In fact, the blades and rackmount systems are precisely those available from Dell, Sun, Apple, etc. You are presenting no evidence, just hypothesizing that your stamp protocol somehow burns out more CPUs than render farms do, than Mersenne prime apps to, than financial simulations do, etc. Yet you present no actual numbers. so, will we see a Pentium IV spontaneously ignite like a third tier heavy-metal group in a Rhode Island nightclub? No, you're right, we won't. I think it's safe to say we will see increasing unreliability, power supply failures, and failures of microelectronics due to increased thermal load. Which is good enough for my purposes. Evidence is desirable, belief is just belief. --Tim May That government is best which governs not at all. --Henry David Thoreau
Re: Skeptical about claim that stamp creation burns out modern CPUs
On Jan 1, 2004, at 11:56 AM, Riad S. Wahby wrote: Tim May [EMAIL PROTECTED] wrote: Now I grant you that I haven't tested CPUs in this way in many years. But I am skeptical that recent CPUs are substantially different than past CPUs. I would like to see some actual reports of burned literally CPUs. I've never seen a burned literally CPU, but I have tracked the demise of an AMD K6 (or K6-2, can't remember now) from hot carrier effects. If all processors were made like that one, you would see a lot more load-induced failures. Just so. A lot of games are close to being CPU-bound, plus the screensavers used as Mersenne prime finders and the like, and there are few reports of house fires caused by the CPU being smoked. When I did reliability stuff for Intel, CPUs failed, but mostly not in ways that had them catching on fire, as the stamp guy is suggesting is common for stamp generation. --Tim May #1. Sanhedrin 59a: Murdering Goyim (Gentiles) is like killing a wild animal. #2. Aboda Sarah 37a: A Gentile girl who is three years old can be violated. #3. Yebamoth 11b: Sexual intercourse with a little girl is permitted if she is three years of age. #4. Abodah Zara 26b: Even the best of the Gentiles should be killed. #5. Yebamoth 98a: All gentile children are animals. #6. Schulchan Aruch, Johre Deah, 122: A Jew is forbidden to drink from a glass of wine which a Gentile has touched, because the touch has made the wine unclean. #7. Baba Necia 114, 6: The Jews are human beings, but the nations of the world are not human beings but beasts.
Skeptical about claim that stamp creation burns out modern CPUs
On Jan 1, 2004, at 8:13 AM, Eric S. Johansson wrote: actually, we mean burned literally. the stamp creation process raises the temperature of the CPU. Most systems are not build for full tilt computational load. They do not have the ventilation necessary for reliable operation. So, they may get by with the first 8-12 hours of stamp generation (i.e. roughly 2000-3000 stamps per machine) but the machine reliability after that time will degrade as the heat builds up. Feel free to run this experiment yourself. Take a cheat machine from your local chop shop, run hashcash in an infinite loop, and wait for the smoke detector to go off. there is nothing quite like waking up to the smell of freshly roasted Intel. I'm skeptical of this claim. A lot of Intel and AMD and similar machines are running full-tilt, 24/7. To wit, Beowulf-type clusters, the Macintosh G5 cluster that is now rated third fasted in the world, and so on. None of these machines is reported to be burning up literally. Likewise, a lot of home and corporate users are running background tasks which are at 100% CPU utilization. (Examples abound, from render farms to financial modeling to... Friends of mine run a bunch of 2 and 3 GHz Pentium 4 machines in CPU-bound apps, and they run them 24/7. (Their company, Invest by Agents, analyzes tens of thousands of stocks. They use ordinary Dells and have had no catastrophic burned literally failures.) Further, junction-to-case temperature in a ceramic package has a time constant of tens of seconds, meaning, the case temperature reaches something like 98% of its equilibrium value (as wattage reaches, say, 60 watts, or whatever), in tens of seconds. (For basic material and physics reasons...I used to make many of these measurements when I was at Intel, and nothing in the recent packaging has changed the physics of heat flow much.) We also used to run CPUs at 125 C ambient, under operating conditions, for weeks at a time. Here the junction temperature was upwards of 185 C. Failures occurred in various ways, usually do to electromigration and things like that. Almost never was there any kind of fire. Just burnout, which is a generic name but has nothing of course to do with burning in the chemical sense. Now I grant you that I haven't tested CPUs in this way in many years. But I am skeptical that recent CPUs are substantially different than past CPUs. I would like to see some actual reports of burned literally CPUs. By the way, I have run some apps on my Macintosh 1 GHz CPU which are CPU-bound. No burn ups. I'd like to see some support for the claim that running a stamp creation process is more likely to burn up a modern machine than all of these apps running financial modeling, render farms, and supercomputer clusters are doing. Until then, render me skeptical. --Tim May
Re: Skeptical about claim that stamp creation burns out modern CPUs
Tim May [EMAIL PROTECTED] wrote: Now I grant you that I haven't tested CPUs in this way in many years. But I am skeptical that recent CPUs are substantially different than past CPUs. I would like to see some actual reports of burned literally CPUs. I've never seen a burned literally CPU, but I have tracked the demise of an AMD K6 (or K6-2, can't remember now) from hot carrier effects. If all processors were made like that one, you would see a lot more load-induced failures. -- Riad Wahby [EMAIL PROTECTED] MIT VI-2 M.Eng
Re: Skeptical about claim that stamp creation burns out modern CPUs
On Jan 1, 2004, at 11:56 AM, Riad S. Wahby wrote: Tim May [EMAIL PROTECTED] wrote: Now I grant you that I haven't tested CPUs in this way in many years. But I am skeptical that recent CPUs are substantially different than past CPUs. I would like to see some actual reports of burned literally CPUs. I've never seen a burned literally CPU, but I have tracked the demise of an AMD K6 (or K6-2, can't remember now) from hot carrier effects. If all processors were made like that one, you would see a lot more load-induced failures. Just so. A lot of games are close to being CPU-bound, plus the screensavers used as Mersenne prime finders and the like, and there are few reports of house fires caused by the CPU being smoked. When I did reliability stuff for Intel, CPUs failed, but mostly not in ways that had them catching on fire, as the stamp guy is suggesting is common for stamp generation. --Tim May #1. Sanhedrin 59a: Murdering Goyim (Gentiles) is like killing a wild animal. #2. Aboda Sarah 37a: A Gentile girl who is three years old can be violated. #3. Yebamoth 11b: Sexual intercourse with a little girl is permitted if she is three years of age. #4. Abodah Zara 26b: Even the best of the Gentiles should be killed. #5. Yebamoth 98a: All gentile children are animals. #6. Schulchan Aruch, Johre Deah, 122: A Jew is forbidden to drink from a glass of wine which a Gentile has touched, because the touch has made the wine unclean. #7. Baba Necia 114, 6: The Jews are human beings, but the nations of the world are not human beings but beasts.
Re: Skeptical about claim that stamp creation burns out modern CPUs
-- On 1 Jan 2004 at 10:44, Tim May wrote: Further, junction-to-case temperature in a ceramic package has a time constant of tens of seconds, meaning, the case temperature reaches something like 98% of its equilibrium value (as wattage reaches, say, 60 watts, or whatever), in tens of seconds. The time constant for the CPU+plus cooling system is a good deal longer, and in modern CPUs the large mass of the cooling system can result in quite long periods, for example a quarter of an hour, before CPU load results in heat related shut off. We also used to run CPUs at 125 C ambient Today's CPUs will generally fail a bit above seventy centigrade. They frequently fail in ways that cause them to draw increased current, eventuallly incinerating the motherboard. To prevent this, always look for the bios option to shut down the motheroboard in the event of CPU overheating. --digsig James A. Donald 6YeGpsZR+nOTh/cGwvITnSR3TdzclVpR0+pr3YYQdkG Uw0lUnQOu8bBc6kOrcDpYZKS0DjzIgrXM9AJSVh2 49rBlWsHg9Teys0ELS5pT26g56P8tEMtp/mQ3eihl
Re: Skeptical about claim that stamp creation burns out modern CPUs
On Jan 1, 2004, at 2:35 PM, Eric S. Johansson wrote: Tim May wrote: I'm skeptical of this claim. A lot of Intel and AMD and similar machines are running full-tilt, 24/7. To wit, Beowulf-type clusters, the Macintosh G5 cluster that is now rated third fasted in the world, and so on. None of these machines is reported to be burning up literally. Likewise, a lot of home and corporate users are running background tasks which are at 100% CPU utilization. I will admit to a degree of skepticism myself even though I am describing overheating as a likely outcome. But what is your actual evidence, as opposed to your belief that overheating is a likely outcome? I have said that I know of many machines (tens of thousands of CPUs, and probably many more I don't know about directly) which are running CPU-bound applications 24/7. I have heard of no burning up literally cases with the many Beowulf clusters, supercomputers, and 24/7 home or business screensavers and crunching apps, so I suspect they are not common. If you have actual evidence, as opposed to likely outcome speculations, please present the evidence. First, if you lose a fan on an Intel CPU of at least Pentium III generation or an AMD equivalent, you will lose your CPU to thermal overload. This is a well-known and well-documented problem. One question is can stamp work thermally overload and damage a CPU. Second question is how much stamp work can you do without thermally overloading the CPU. This is true whether one is running Office or a stamp program. You are just repeating a general point about losing a fan, not about stamp generation per se. Boxer fan lifetimes are usually about comparable to hard drive lifetimes, which also kill a particular machine. You are not presenting anything new here, and the association with stamp generation is nonexistent. Large clusters have more careful thermal engineering applied to them than probably most of the zombies out there. I have seen one Beowulf cluster constructed out of standard 1U chassis, motherboards, fans etc. and frequently 10 percent of the systems are down at any one time. The vast majority of the failures have been due to thermal problems. Most clusters use exactly the same air-cooled machines as are available from Dell, Sun, Apple, etc. In fact, the blades and rackmount systems are precisely those available from Dell, Sun, Apple, etc. You are presenting no evidence, just hypothesizing that your stamp protocol somehow burns out more CPUs than render farms do, than Mersenne prime apps to, than financial simulations do, etc. Yet you present no actual numbers. so, will we see a Pentium IV spontaneously ignite like a third tier heavy-metal group in a Rhode Island nightclub? No, you're right, we won't. I think it's safe to say we will see increasing unreliability, power supply failures, and failures of microelectronics due to increased thermal load. Which is good enough for my purposes. Evidence is desirable, belief is just belief. --Tim May That government is best which governs not at all. --Henry David Thoreau
