(Why) is vanitygen less resource-intensive than mining?

[Lorenzo]

As I understand it, vanitygen works in a very similar way to standard Bitcoin mining. Both processes use either the CPU or the GPU to solve SHA-256 hashes. And yet, when I run vanitygen on my laptop, it can do so for days on end with no excessive overheating and little performance impact. I've never tried mining on my laptop before but it seems to be universally discouraged because it is said that any laptops that do mine will inevitably overheat and fail. This also seems to be true for mining non-SHA-256 coins where no ASIC currently exists.

I have a fairly basic understanding of how vanitygen and Bitcoin mining are similar, as well as how they differ. With vanitygen, you look for a private key that corresponds to a desired address. To do this, you find the SHA-256 hash of the private key. If it doesn't correspond to an address you're looking for, then it moves onto the next one. With mining, you hash the block header repeatedly, changing one parameter until you find a specified target. Both processes use the SHA-256 hashing algorithm.

So why can I run vanitygen for four days straight with my laptop staying cool and yet I can't mine cryptocurrencies like Darkcoin (or Bitcoin before ASICs) with the same laptop?

[OgNasty]

As I understand it, vanitygen works in a very similar way to standard Bitcoin mining. Both processes use either the CPU or the GPU to solve SHA-256 hashes. And yet, when I run vanitygen on my laptop, it can do so for days on end with no excessive overheating and little performance impact. I've never tried mining on my laptop before but it seems to be universally discouraged because it is said that any laptops that do mine will inevitably overheat and fail. This also seems to be true for mining non-SHA-256 coins where no ASIC currently exists.

I have a fairly basic understanding of how vanitygen and Bitcoin mining are similar, as well as how they differ. With vanitygen, you look for a private key that corresponds to a desired address. To do this, you find the SHA-256 hash of the private key. If it doesn't correspond to an address you're looking for, then it moves onto the next one. With mining, you hash the block header repeatedly, changing one parameter until you find a specified target. Both processes use the SHA-256 hashing algorithm.

So why can I run vanitygen for four days straight with my laptop staying cool and yet I can't mine cryptocurrencies like Darkcoin (or Bitcoin before ASICs) with the same laptop?

You can mine on your laptop.  The problem isn't keeping it cool if it can run vanitygen without overheating.  The problem is that your laptop isn't powerful enough to mine enough coins to pay for the electricity it's using.  Hope that helps.

[TheRealSteve]

Just to expand a bit on OgNasty's to-the-point reply:

As you mention, you haven't actually tried to mine Bitcoins on that laptop - but if you did, you would find that the CPU/GPU load is very similar.  So there's no difference between mining Bitcoins and generating vanity addresses as far as load and associated temperature goes.
There might be some difference when using certain altcoins - either because the mining process hasn't been optimized as far, or because there's parts of the mining process that don't depend on processor-intensive bits. No idea if Darkcoin belongs in that category.

High temps will invariably shorten the lifespan of components no matter how that high temp is attained, which is why it's generally discouraged - especially since CPU/GPU mining of Bitcoin is, nowadays, pointless beyond any educational purposes. ( See OgNasty's reply )
There's some additional trouble if the temperature is allowed to fluctuate wildly as materials expand/contract repeatedly.
However, there's little indication as to how much lifespan is shortened, and how much lifespan a CPU/GPU has to begin with.  Some laptops crap out well within 6 months even if just used for non-intensive things, and some laptops go on for 10 years+ while under load all the time.  Say its lifespan is shortened by 2 years, but that's still well after you sell the thing on craigslist in favor of a newer laptop, then why care?  Of course if it does die on you while you're still making good use of it, but is outside warranty, that does suck.  Back in the day, CPU/GPU mining Bitcoin was a calculated risk.  Now you'd be silly to do so.  So it's not that you can't, it's just that you shouldn't.

Note that any well-engineered computer doesn't really 'overheat' to the point of immediate catastrophic damage anymore.  Fans will spin up, CPUs and GPUs throttle down if they're starting to get too hot, and the machine will power down if all of that doesn't help.

Throwing this back to vanitygen - If you do feel that high loads are a concern, you can always tell programs to ease off a bit.  oclvanitygen's 'threads' parameter helps lower load on the GPU, while the CPU version can be moderated a bit using 'cpulimit' or 'battle encoder shirase' depending on platform.  Can even make that temperature-dependent, if bored.