_tk wrote on 2022-11-29, 06:54:As was mentioned, overclocking a Pentium MMX was pretty common back in the day. We all know that it works and what can be done. […]
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Paadam wrote on 2022-11-29, 06:38:
Funny to see that most people who say don't do it only say it based on nothing than theory (which isn't wrong in itself but certainly does not apply to specific case). But I guess it is always that way: there are people who talk and there are people who do 😀
As was mentioned, overclocking a Pentium MMX was pretty common back in the day. We all know that it works and what can be done. We've done it, period.
However, it's now 25+ years later and thus those same electronics are 25+ years old. Will it still work? Likely, assuming all parts are still within spec. Is it a good idea? Debatable. I'm not going to run any of my MMX processors at an overclock anymore because, as said, PII/PIII parts from that era are still relatively cheap and faster than an overclocked MMX will ever be. And I've owned my MMX processors since new and frying them doing a silly overclock is not something I want to do.
Otherwise, do you have any experience or knowledge to add to this?
There is no theory about this. Chips are designed with margin for manufacturing purposes, first, and a max speed spec, likely as advertised. They can also tolerate small swings in voltage too. Whether it was designed for max 233 mhz, 250 mhz, who knows. But running both higher voltage and higher speed that the public spec could be not intended. If they did, then they would have sold a 100mhz fsb capable chip.
I made a bit of a mistake though when I was thinking about it earlier. I was speaking about 2.8V IO, but the chip is obviously 3.3V IO. It's the core voltage being overvolted to support 100mhz fsb and giving an overclock. I wouldn't do that, and that is because of the physical design of the gates inside. If 2.8V was the max core spec, then I wouldn't for sure go above 2.92V, which who knows if the voltage regulator and demands on that core VDD will give you a perfect 2.9V. And pushing the chip, you may eventually burn out the large drivers inside the chip due to electromigration, or overheat just a part of the chip that produces more heat than normal. So if some people have chips that aren't exactly stable at 2.9V with 100mhz fsb, then you know these chips are at their limit.
I do admit that overclocking was pretty common on these chips back in the day.