4 ms·

> Each MMX register is 64 bits wide. Internally, the MMX registers were aliases of the x87 floating-point registers. Due to the way the first Pentium 3 CPUs (K

> Each MMX register is 64 bits wide. Internally, the MMX registers were aliases of the x87 floating-point registers. Due to the way the first Pentium 3 CPUs (Katmai) were built, they likewise aliased the x87 (and thus, MMX) registers to the XMM SSE registers, but this was hidden from programs. It wasn't until at least the Coppermine revision that they were separate registers again.

Nition 2mo ago
I remember hearing a rumour as a young teen that the Coppermine codename meant it actually had copper wiring and that's what made it faster somehow. Copper has lower resistance than aluminium and can therefore help chips run faster - it makes sense! But it was just a codename and the coppermine had aluminium interconnects. My family got a PIII 533Mhz coppermine, in the early sideways Slot 1 configuration. Blazing fast at the time. Been a long time since I heard anyone say "coppermine". CPU progress was wild in the 90s, where you could wait two years and your new CPU would be double the old one's speed at the same price point. Today it takes near a decade for CPU speed to double. I also recall the first game that advertised its exciting use of the new MMX technology: POD.[1] [1] https://en.wikipedia.org/wiki/POD_(video_game) https://en.wikipedia.org/wiki/POD_(video_game)
- Lerc 2mo ago
  Copper interconnects might have been introduced around then, but I suspect the naming is more coincidental than anything. I remember just after IBM got copper interconnects working, there was a stock market dive, I ranted to my partner about how crazy it is for a company to achieve a sought after goal and have its value decrease. The next day there was a news story about the entire market decline being stalled by the force of IBM buying back it's own shares. My partner told me I should rant less and invest more.
  - Nition 2mo ago
    Haha, yeah the rumour came around at a time when there was real work going on with copper interconnects which just confused the situation, but the coppermine didn't use them.
- moosedev 2mo ago
  (Code)named after https://en.wikipedia.org/wiki/Coppermine_River https://en.wikipedia.org/wiki/Coppermine_River , apparently. POD was pretty rad :) Thanks for the reminder of it (and all the MMX marketing around it.)
- 245425456g 2mo ago
  P3 Coppermine was 0.18 µm. P3 Tualatin was 0.13 µm with Cu and low-K. So no, Coppermine had nothing to do with Cu in the process.
  - Nition 2mo ago
    Wow, I never knew they actually did switch to copper on the next model. What a missed naming opportunity.
- wormius 2mo ago
  C-f "pod" There it is :)
- rzzzt 2mo ago
  The one I've read is that Tualatin comes from "too late in" i.e. a model introduced too late in the process/architecture lifecycle to be profitable.
- easyThrowaway 2mo ago
  Ironically P.o.d. didn't really use MMX at all except for Dolby Surround decoding[1]. [1]https://retromediahub.com/index.php/Pod:_Planet_of_Death https://retromediahub.com/index.php/Pod:_Planet_of_Death
  - Nition 2mo ago
    Your link says that Dolby Surround is one feature that won't work at all without MMX on, but doesn't go so far as to say that it's the only feature that's enhanced with MMX (it uses phrasing like "MMX‑dependent features such as Dolby Surround"). I'm not saying you're wrong, but your link doesn't confirm your statement either. Doesn't look like there's any conclusive info out there, so probably someone needs to actually decompile it and look for MMX opcodes.
    - easyThrowaway 2mo ago
      I remember one of the original developers explaining in a blog post that MMX support came right before the original release and was added just for Dolby Surround, unfortunately can't find it anywhere. The remaining references available regarding this factoid are incredibly ancient, too: - https://groups.google.com/g/comp.sys.ibm.pc.games.misc/c/MRFVtFryiqU/m/-KhH9DX5dpAJ https://groups.google.com/g/comp.sys.ibm.pc.games.misc/c/MRF... - https://www.mobygames.com/game/644/pod/user-review/2384353/ https://www.mobygames.com/game/644/pod/user-review/2384353/ No idea if any additional support was added in one of the subsequent releases.
- _the_inflator 2mo ago
  Game makers started to utilize Moore’s Law and produced games, that required actual hardware. During the 00ish years it felt like your system gets killed by a new game. With the advent of the online update some game makers went way to far, Gothic in Europe was a pre-alpha release that never really got finalized but was really anticipated by gamers here. I stopped buying games, since this was a rat race. Everything was evolving and with the utilization of the GForce CPU gaming reached a new hardware design phase where CPU, bus (!), ram, essentially everything had to be finetuned otherwise you would run into massive performance penalties so to say. The term bottleneck wasn’t used back then but describes very clearly the dilemma back then. In essence everything was getting more expensive while design considerations were critical. And the systems were so fragile. Some boards couldn’t handle Intel’s cooling demand for the CPU, it was a crazy time. I remember the infamous AMD diss that led the company somewhat to the top tier their were then with the Athlon, when a dude filmed what happens during runtime when you remove the heat fan from an Intel vs. AMD. Weird time, glad it is over. So much hardware and money burned.
userbinator 2mo ago
It makes it easier to save and restore state when it's basically the same registers used differently.
- Sesse__ 2mo ago
  Yes. Which matters a lot when you cannot just update OS kernels willy-nilly (most people did not have Internet connectivity, Windows Update did not exist before Windows 98).
245425456g 2mo ago
No, x87/MMX and SSE XMM were not aliased. They were two separate register files. (You may be confusing it with XMM vs YMM vs ZMM, i.e. SSE vs AVX vs AVX512.)
- deaddodo 2mo ago
  It’s more likely they’re confusing it with 3DNow! (AMD’s own media extension focused on floating point math). That was strictly aliased and therefore an either/or situation on chips that had both.
  - 45t345tg35 2mo ago
    Sure, 3DNow! operated on MMX registers. But the OP was talking about Intel's P3... so 3DNow! wasn't a factor...
    - deaddodo 2mo ago
      I think we’re agreeing. I think they’re mixing up the 3DNow introduction with the SSE one and conflating them into one. SSE never had aliasing, so OP’s comment is strictly incorrect either way.
Agingcoder 2mo ago
I got bitten by that one - I remember my 3d engine going all wrong because I hadn’t realized I couldn’t mix mmx and fpu registers unless I was willing to pay for the extraordinarily expensive EMMS (?) instruction

Nition 2mo ago

I remember hearing a rumour as a young teen that the Coppermine codename meant it actually had copper wiring and that's what made it faster somehow. Copper has lower resistance than aluminium and can therefore help chips run faster - it makes sense! But it was just a codename and the coppermine had aluminium interconnects. My family got a PIII 533Mhz coppermine, in the early sideways Slot 1 configuration. Blazing fast at the time. Been a long time since I heard anyone say "coppermine". CPU progress was wild in the 90s, where you could wait two years and your new CPU would be double the old one's speed at the same price point. Today it takes near a decade for CPU speed to double. I also recall the first game that advertised its exciting use of the new MMX technology: POD.[1] [1] https://en.wikipedia.org/wiki/POD_(video_game) https://en.wikipedia.org/wiki/POD_(video_game)

Lerc 2mo ago
Copper interconnects might have been introduced around then, but I suspect the naming is more coincidental than anything. I remember just after IBM got copper interconnects working, there was a stock market dive, I ranted to my partner about how crazy it is for a company to achieve a sought after goal and have its value decrease. The next day there was a news story about the entire market decline being stalled by the force of IBM buying back it's own shares. My partner told me I should rant less and invest more.
- Nition 2mo ago
  Haha, yeah the rumour came around at a time when there was real work going on with copper interconnects which just confused the situation, but the coppermine didn't use them.
moosedev 2mo ago
(Code)named after https://en.wikipedia.org/wiki/Coppermine_River https://en.wikipedia.org/wiki/Coppermine_River , apparently. POD was pretty rad :) Thanks for the reminder of it (and all the MMX marketing around it.)
245425456g 2mo ago
P3 Coppermine was 0.18 µm. P3 Tualatin was 0.13 µm with Cu and low-K. So no, Coppermine had nothing to do with Cu in the process.
- Nition 2mo ago
  Wow, I never knew they actually did switch to copper on the next model. What a missed naming opportunity.
wormius 2mo ago
C-f "pod" There it is :)
rzzzt 2mo ago
The one I've read is that Tualatin comes from "too late in" i.e. a model introduced too late in the process/architecture lifecycle to be profitable.
easyThrowaway 2mo ago
Ironically P.o.d. didn't really use MMX at all except for Dolby Surround decoding[1]. [1]https://retromediahub.com/index.php/Pod:_Planet_of_Death https://retromediahub.com/index.php/Pod:_Planet_of_Death
- Nition 2mo ago
  Your link says that Dolby Surround is one feature that won't work at all without MMX on, but doesn't go so far as to say that it's the only feature that's enhanced with MMX (it uses phrasing like "MMX‑dependent features such as Dolby Surround"). I'm not saying you're wrong, but your link doesn't confirm your statement either. Doesn't look like there's any conclusive info out there, so probably someone needs to actually decompile it and look for MMX opcodes.
  - easyThrowaway 2mo ago
    I remember one of the original developers explaining in a blog post that MMX support came right before the original release and was added just for Dolby Surround, unfortunately can't find it anywhere. The remaining references available regarding this factoid are incredibly ancient, too: - https://groups.google.com/g/comp.sys.ibm.pc.games.misc/c/MRFVtFryiqU/m/-KhH9DX5dpAJ https://groups.google.com/g/comp.sys.ibm.pc.games.misc/c/MRF... - https://www.mobygames.com/game/644/pod/user-review/2384353/ https://www.mobygames.com/game/644/pod/user-review/2384353/ No idea if any additional support was added in one of the subsequent releases.
_the_inflator 2mo ago
Game makers started to utilize Moore’s Law and produced games, that required actual hardware. During the 00ish years it felt like your system gets killed by a new game. With the advent of the online update some game makers went way to far, Gothic in Europe was a pre-alpha release that never really got finalized but was really anticipated by gamers here. I stopped buying games, since this was a rat race. Everything was evolving and with the utilization of the GForce CPU gaming reached a new hardware design phase where CPU, bus (!), ram, essentially everything had to be finetuned otherwise you would run into massive performance penalties so to say. The term bottleneck wasn’t used back then but describes very clearly the dilemma back then. In essence everything was getting more expensive while design considerations were critical. And the systems were so fragile. Some boards couldn’t handle Intel’s cooling demand for the CPU, it was a crazy time. I remember the infamous AMD diss that led the company somewhat to the top tier their were then with the Athlon, when a dude filmed what happens during runtime when you remove the heat fan from an Intel vs. AMD. Weird time, glad it is over. So much hardware and money burned.

userbinator 2mo ago

It makes it easier to save and restore state when it's basically the same registers used differently.

Sesse__ 2mo ago
Yes. Which matters a lot when you cannot just update OS kernels willy-nilly (most people did not have Internet connectivity, Windows Update did not exist before Windows 98).

245425456g 2mo ago

No, x87/MMX and SSE XMM were not aliased. They were two separate register files. (You may be confusing it with XMM vs YMM vs ZMM, i.e. SSE vs AVX vs AVX512.)

deaddodo 2mo ago
It’s more likely they’re confusing it with 3DNow! (AMD’s own media extension focused on floating point math). That was strictly aliased and therefore an either/or situation on chips that had both.
- 45t345tg35 2mo ago
  Sure, 3DNow! operated on MMX registers. But the OP was talking about Intel's P3... so 3DNow! wasn't a factor...
  - deaddodo 2mo ago
    I think we’re agreeing. I think they’re mixing up the 3DNow introduction with the SSE one and conflating them into one. SSE never had aliasing, so OP’s comment is strictly incorrect either way.

Agingcoder 2mo ago

I got bitten by that one - I remember my 3d engine going all wrong because I hadn’t realized I couldn’t mix mmx and fpu registers unless I was willing to pay for the extraordinarily expensive EMMS (?) instruction