4 ms·

The vast majority of computers were commodity boxes that are extremely well documented, emulated, and the ones that exist today are in private collections. The

The vast majority of computers were commodity boxes that are extremely well documented, emulated, and the ones that exist today are in private collections. The interesting stuff is also being held by private collectors in large amounts. Around 2000-2010, a lot of the interesting 80s and 90s stuff started becoming cheap and was snapped up by any interested party, the rest was landfilled. If you are getting into this now, you are too late - hit up ebay and pay inflated prices. Speaking of landfills, most of those computers had RTC on board, and were powered by batteries, which tend to explode and "rot" away the board. It's likely very few of them will be salvageable in an easy-to-repair way if they sit for another 20 years.

TacticalCoder 4y ago
> Speaking of landfills, most of those computers had RTC on board, and were powered by batteries, which tend to explode and "rot" away the board. It's likely very few of them will be salvageable in an easy-to-repair way if they sit for another 20 years. Yup. During the lockdown I had time to waste and checked various YouTube videos and they scared me enough that I started checking my old computers for batteries. Found one in an old Apple computer (I forgot if it's a Classic or Classic II or Plus: one of those "inside" a 9" CRT) and indeed the battery had started leaking. I took it out, cleaned what I could, and the computer was still working. But a few more years and it would have been badly damaged. And it's not just batteries: capacitors may sometimes start leaking and destroying the PCB too.
srvmshr 4y ago
Slightly OT: But do modern computers have RTC? If not, how is time keeping done?
- johnwalkr 4y ago
  Yes, they still do.
  - srvmshr 4y ago
    So is the RTC battery still a problem in modern computers?
    - kalleboo 4y ago
      Yes, but modern computers tend to use CR2032 batteries that are less prone to leaking. Or they're laptops which have their own battery issues (swelling and fire)
    - amelius 4y ago
      I've noticed that some motherboards power the clock through mains power even when turned off.
      - exmadscientist 4y ago
        This is desirable because the mains frequency is much more accurate, long-term, than the crystal frequency. So the very best designs use a design which is mains powered as much as possible, even using a rechargeable lithium coin cell that is slowly recharged whenever mains is available, but then switch over to the crystal when no mains is available.
        charles_kaw 4y ago
        accuracy isnt really important anymore for consumer gear - as long as it's accurate enough to have the month right over a few years of inactivity, it'll pass the certificate checks required to do ntp over ssl - which most modern systems do by default
        exmadscientist 4y ago
        That's only applicable for systems with a network connection. Many things still don't and shouldn't.
        4y ago
the_only_law 4y ago
> hit up ebay and pay inflated prices. Alternatively get involved the with retrocomputing communities. A lot of people are much more reasonable about prices, especially some of the more knowledgeable people I've met. I'll probably be selling off an SGI Indy and some T1/E1/Telecom equipment soon. But yeah, anything particularly cool or pre-80s I've lost a lot of money on ebay. Occasionally a neat deal. I got a fully working very nice condition X-terminal for like $20 and got it (inconsistently) working with a modern Linux server over modern Ethernet LAN.

TacticalCoder 4y ago

> Speaking of landfills, most of those computers had RTC on board, and were powered by batteries, which tend to explode and "rot" away the board. It's likely very few of them will be salvageable in an easy-to-repair way if they sit for another 20 years. Yup. During the lockdown I had time to waste and checked various YouTube videos and they scared me enough that I started checking my old computers for batteries. Found one in an old Apple computer (I forgot if it's a Classic or Classic II or Plus: one of those "inside" a 9" CRT) and indeed the battery had started leaking. I took it out, cleaned what I could, and the computer was still working. But a few more years and it would have been badly damaged. And it's not just batteries: capacitors may sometimes start leaking and destroying the PCB too.

srvmshr 4y ago

Slightly OT: But do modern computers have RTC? If not, how is time keeping done?

johnwalkr 4y ago
Yes, they still do.
- srvmshr 4y ago
  So is the RTC battery still a problem in modern computers?
  - kalleboo 4y ago
    Yes, but modern computers tend to use CR2032 batteries that are less prone to leaking. Or they're laptops which have their own battery issues (swelling and fire)
  - amelius 4y ago
    I've noticed that some motherboards power the clock through mains power even when turned off.
    - exmadscientist 4y ago
      This is desirable because the mains frequency is much more accurate, long-term, than the crystal frequency. So the very best designs use a design which is mains powered as much as possible, even using a rechargeable lithium coin cell that is slowly recharged whenever mains is available, but then switch over to the crystal when no mains is available.
      - charles_kaw 4y ago
        accuracy isnt really important anymore for consumer gear - as long as it's accurate enough to have the month right over a few years of inactivity, it'll pass the certificate checks required to do ntp over ssl - which most modern systems do by default
        exmadscientist 4y ago
        That's only applicable for systems with a network connection. Many things still don't and shouldn't.
        4y ago

the_only_law 4y ago

> hit up ebay and pay inflated prices. Alternatively get involved the with retrocomputing communities. A lot of people are much more reasonable about prices, especially some of the more knowledgeable people I've met. I'll probably be selling off an SGI Indy and some T1/E1/Telecom equipment soon. But yeah, anything particularly cool or pre-80s I've lost a lot of money on ebay. Occasionally a neat deal. I got a fully working very nice condition X-terminal for like $20 and got it (inconsistently) working with a modern Linux server over modern Ethernet LAN.