5 ms·

What? Silicone hardware generates heat. Neither silicone hardware nor tube hardware goes literally cold in a cold boot; just the power is cut for a moment, us

What? Silicone hardware generates heat. Neither silicone hardware nor tube hardware goes literally cold in a cold boot; just the power is cut for a moment, usually not long enough to lose a lot of heat.

tass 2y ago
I imagine these terms could have changed over time, but consider that a warm boot might have meant power off and on with these old computers. One difference is that the valves have more chance of burning out on a cold boot due to the temperature change.
- jaystraw 2y ago
  in the music world, variacs are used to bring old tube amplifiers up to power slowly for that reason. not after being repaired or refurbished generally, but certainly when the amp's condition is unknown. the author of tfa said his new power supplies do that automatically, which is pretty neat.
- kazinator 2y ago
  Filaments experience a high inrush current on startup because their resistance is lower when they are cold. That's why incandescent bulbs often burn out on powerup, rather than in the middle of a duty cycle. Tube filaments last a good long time though, particularly in small signal tubes. They do not shine like light bulb filaments; they glow red. The circuit designer also has a say in it; tube filaments can be operated over a range of currents: you can run tubes hotter or colder. In a digital application, you'd probably want to go as cold as you can get away with for longer life. Tubes have various modes of failure in addition to burned out filaments, like "gassing out", or the cathode emission decreasing, eroding the gain. Of course, abnormal conditions like parts melting from overcurrent. Speaking of incandescent bulbs: those are victims of planned obsolescence. A bulb can easily be made that will last 50 years; it's just not profitable because you can't charge 50 times more for it than one that burns out in a year. Once everyone has 50 year bulbs, you're out of business.
  - ekidd 2y ago
    > Once everyone has 50 year bulbs, you're out of business. This seems to have been the issue with the expensive Philips Hue LED bulbs (the ZigBee ones). We installed ours close to a decade ago, and we took them with us when we moved to a new house. I don't think I've replaced a single one yet. Philips seems to have de-emphasized that set of bulbs in favor of cheaper models, as far as I can tell?
    - kazinator 2y ago
      I have 13-y-o Phillips LED flood lights in some track lighting (50W equivalents, maybe?). Working great!
01HNNWZ0MV43FF 2y ago
Silicon. Silicone is the plastic used to make crummy kitchen utensils
- Doxin 2y ago
  Silicone is a rubber made to make good kitchen utensils. The crummy plastic ones tend to be nylon or the like. Biggest tell is that silicone does not melt.
- kazinator 2y ago
  I'm amazed I made the typo twice in the same post. Kazinator comments containing "silicone": https://hn.algolia.com/?dateRange=all&page=0&prefix=false&query=kazinator%20silicone&sort=byDate&type=comment https://hn.algolia.com/?dateRange=all&page=0&prefix=false&qu... Kazinator comments using "silicon" https://hn.algolia.com/?dateRange=all&page=0&prefix=false&query=kazinator%20silicon&sort=byDate&type=comment https://hn.algolia.com/?dateRange=all&page=0&prefix=false&qu...
  - klyrs 2y ago
    > kazinator|7 years ago ... Love the irony of how silicon is used. Common confusion; silicon is a metalloid, irony is metallic
  - hilbert42 2y ago
    Take heart, you're not alone, my WP's speller has automatically corrected to 'silicone' on more than one occasion and I've not noticed the embarrassing mistake. ;-)
082349872349872 2y ago
First boot in the morning was cold, and —the hardware having literally been cold— took minutes longer than subsequent, warm, boots.
- kazinator 2y ago
  That wouldn't be on account of the tubes; tube filaments do not take minutes to heat up the cathodes. Warm boots can save time by not repeating all the boostrapping steps. In a warm boot, you typically don't execute any power-on self-checks, for starters.
  - 082349872349872 2y ago
    Maybe I'm misremembering (I was very young) or maybe I was with people who were too superstitious, but these tubes themselves were actually from the 1950s, and they did indeed take a significant amount of time before they decided the hardware was "warm enough" that one could let the software start doing its thing.
cjs_ac 2y ago
The difference is that for solid-state logic, the heat is purely a waste byproduct, whereas for thermionic valves, the heat is the energy used by the electrons to move between the electrodes, hence the name. If the valves are cold, you have to wait for them to warm up before they can do anything.
- kazinator 2y ago
  All the same, "cold boot" doesn't refer to letting tubes cool down. If power is restored while the tubes are still hot, it's still a "cold boot". The electrons are not moved by heat; they are moved by the electric potential between the electrodes. The heat goes into maintaining the cathode at a certain temperature, at which the electrons "boil off" in sufficient numbers, but that requires only a smidgeon of the energy. Though depending on it, tubes are incredibly wasteful of heat. So you say silicon and other parts don't require heat? Check that data sheet again! If the part's operating range is from -40°C to 70°C, then that part requires heat. If the ambient temperature happens to be -100°C, you have to heat it, perhaps by installing a heating filament into the chassis. E.g. check the TI datasheet for the NE5532 op-amps: Free air operating temperature: NE5532, NE5532A: 0 to 70°C. SA5532, SA5532A: –40 to 85°C. (That standard part is quite delicate there, only down to zero!) Conversely, thermionic tubes for a hot environment could be built without heating filaments. If the ambient temperature is 500°C, and that happens to be quite enough for that tube's cathode, then it Just Works, like your NE5532 IC at 3°C.
  - Max-q 2y ago
    The valves need to be warmed up can still be the source of the names "cold boot" and "warm boot", even if we today have given them different meaning.
    - kazinator 2y ago
      The meanings we give them today go back almost 50 years. Then the trail runs cold, pardon the pun. According to Google n-gram searches, "cold reboot" and "warm reboot" didn't exist at all until the late 1970s. Related terms like "cold boot" and "warm boot" come up, but only in references to footwear. Can't find any computer uses 1950-1970. The "cold start" and "warm start" mostly come up in automotive, aviation or marine contexts, confounding the search. Likewise, not finding computer uses. Not finding computer uses for "cold restart" and "warm restart", either. All these terms take off as computer terms in the late 1970's. By the way, an important feature of the warm reboot is (possibly) that data is still in memory (if you have the kind of machine whose memory is wiped when power is cut, not magnetic core). In machines with simple operating systems, you could recover your program or data from memory after a reset. (I think the timeline in the n-grams coincides with the explosion in microcomputing and reflects that: penetration of the jargon into mainstream writing. Nevertheless, the case doesn't seem to be good though for a vacuum tube origin of warm {start/restart/reboot}.)

tass 2y ago

I imagine these terms could have changed over time, but consider that a warm boot might have meant power off and on with these old computers. One difference is that the valves have more chance of burning out on a cold boot due to the temperature change.

jaystraw 2y ago
in the music world, variacs are used to bring old tube amplifiers up to power slowly for that reason. not after being repaired or refurbished generally, but certainly when the amp's condition is unknown. the author of tfa said his new power supplies do that automatically, which is pretty neat.
kazinator 2y ago
Filaments experience a high inrush current on startup because their resistance is lower when they are cold. That's why incandescent bulbs often burn out on powerup, rather than in the middle of a duty cycle. Tube filaments last a good long time though, particularly in small signal tubes. They do not shine like light bulb filaments; they glow red. The circuit designer also has a say in it; tube filaments can be operated over a range of currents: you can run tubes hotter or colder. In a digital application, you'd probably want to go as cold as you can get away with for longer life. Tubes have various modes of failure in addition to burned out filaments, like "gassing out", or the cathode emission decreasing, eroding the gain. Of course, abnormal conditions like parts melting from overcurrent. Speaking of incandescent bulbs: those are victims of planned obsolescence. A bulb can easily be made that will last 50 years; it's just not profitable because you can't charge 50 times more for it than one that burns out in a year. Once everyone has 50 year bulbs, you're out of business.
- ekidd 2y ago
  > Once everyone has 50 year bulbs, you're out of business. This seems to have been the issue with the expensive Philips Hue LED bulbs (the ZigBee ones). We installed ours close to a decade ago, and we took them with us when we moved to a new house. I don't think I've replaced a single one yet. Philips seems to have de-emphasized that set of bulbs in favor of cheaper models, as far as I can tell?
  - kazinator 2y ago
    I have 13-y-o Phillips LED flood lights in some track lighting (50W equivalents, maybe?). Working great!

01HNNWZ0MV43FF 2y ago

Silicon. Silicone is the plastic used to make crummy kitchen utensils

Doxin 2y ago
Silicone is a rubber made to make good kitchen utensils. The crummy plastic ones tend to be nylon or the like. Biggest tell is that silicone does not melt.
kazinator 2y ago
I'm amazed I made the typo twice in the same post. Kazinator comments containing "silicone": https://hn.algolia.com/?dateRange=all&page=0&prefix=false&query=kazinator%20silicone&sort=byDate&type=comment https://hn.algolia.com/?dateRange=all&page=0&prefix=false&qu... Kazinator comments using "silicon" https://hn.algolia.com/?dateRange=all&page=0&prefix=false&query=kazinator%20silicon&sort=byDate&type=comment https://hn.algolia.com/?dateRange=all&page=0&prefix=false&qu...
- klyrs 2y ago
  > kazinator|7 years ago ... Love the irony of how silicon is used. Common confusion; silicon is a metalloid, irony is metallic
- hilbert42 2y ago
  Take heart, you're not alone, my WP's speller has automatically corrected to 'silicone' on more than one occasion and I've not noticed the embarrassing mistake. ;-)

082349872349872 2y ago

First boot in the morning was cold, and —the hardware having literally been cold— took minutes longer than subsequent, warm, boots.

kazinator 2y ago
That wouldn't be on account of the tubes; tube filaments do not take minutes to heat up the cathodes. Warm boots can save time by not repeating all the boostrapping steps. In a warm boot, you typically don't execute any power-on self-checks, for starters.
- 082349872349872 2y ago
  Maybe I'm misremembering (I was very young) or maybe I was with people who were too superstitious, but these tubes themselves were actually from the 1950s, and they did indeed take a significant amount of time before they decided the hardware was "warm enough" that one could let the software start doing its thing.

cjs_ac 2y ago

The difference is that for solid-state logic, the heat is purely a waste byproduct, whereas for thermionic valves, the heat is the energy used by the electrons to move between the electrodes, hence the name. If the valves are cold, you have to wait for them to warm up before they can do anything.

kazinator 2y ago
All the same, "cold boot" doesn't refer to letting tubes cool down. If power is restored while the tubes are still hot, it's still a "cold boot". The electrons are not moved by heat; they are moved by the electric potential between the electrodes. The heat goes into maintaining the cathode at a certain temperature, at which the electrons "boil off" in sufficient numbers, but that requires only a smidgeon of the energy. Though depending on it, tubes are incredibly wasteful of heat. So you say silicon and other parts don't require heat? Check that data sheet again! If the part's operating range is from -40°C to 70°C, then that part requires heat. If the ambient temperature happens to be -100°C, you have to heat it, perhaps by installing a heating filament into the chassis. E.g. check the TI datasheet for the NE5532 op-amps: Free air operating temperature: NE5532, NE5532A: 0 to 70°C. SA5532, SA5532A: –40 to 85°C. (That standard part is quite delicate there, only down to zero!) Conversely, thermionic tubes for a hot environment could be built without heating filaments. If the ambient temperature is 500°C, and that happens to be quite enough for that tube's cathode, then it Just Works, like your NE5532 IC at 3°C.
- Max-q 2y ago
  The valves need to be warmed up can still be the source of the names "cold boot" and "warm boot", even if we today have given them different meaning.
  - kazinator 2y ago
    The meanings we give them today go back almost 50 years. Then the trail runs cold, pardon the pun. According to Google n-gram searches, "cold reboot" and "warm reboot" didn't exist at all until the late 1970s. Related terms like "cold boot" and "warm boot" come up, but only in references to footwear. Can't find any computer uses 1950-1970. The "cold start" and "warm start" mostly come up in automotive, aviation or marine contexts, confounding the search. Likewise, not finding computer uses. Not finding computer uses for "cold restart" and "warm restart", either. All these terms take off as computer terms in the late 1970's. By the way, an important feature of the warm reboot is (possibly) that data is still in memory (if you have the kind of machine whose memory is wiped when power is cut, not magnetic core). In machines with simple operating systems, you could recover your program or data from memory after a reset. (I think the timeline in the n-grams coincides with the explosion in microcomputing and reflects that: penetration of the jargon into mainstream writing. Nevertheless, the case doesn't seem to be good though for a vacuum tube origin of warm {start/restart/reboot}.)