Reply 800 of 825, by PC@LIVE
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A problem of the older S.7, is in the case of CPU update, the too much heat produced by the linear regulators, let's say that beyond a certain frequency, it is not possible to go, more or less this frequency is 266-300 MHz, but the use of a large heatsink (maybe with a fan), can make the PC usable, but if we want to go faster?
I think it depends on the CPU used, discarding the Intel CPUs, because there are no Pentium MMX over 300 MHz, and leaving out the various Cyrix, because they work with a maximum frequency less than 300 MHz, the only CPU that allows frequencies of 400-500 MHz, is the AMD K6, there are several versions, but the most common are the K6-2 CXT, which have the function that remaps 2X to 6X, a function also present in the versions following this, so versions + and III.
I would avoid using in the S.7 with linear regulators, those that absorb a lot of energy (W), let's see if the use of a low-power CPU can be a solution?
Maybe yes, if we find something from about 10W, but they usually require low VCORE, even less than 2.0V, instead of 2.2V, although motherboards with linear regulators may not go below 2.8V, or at most reach 2.5V.
So reducing the voltage, solves or not the problem of too much heat generated by the linear regulator? Probably not!
And without resorting to adapters with an on-board regulator, how can it be done?
The solution could be a modification, linear regulators usually use +5V, to lower to about +3V, so what could be done?
A solution could be to replace +5V with +3.3V, so the starting voltage would be +3.3V, which would then be reduced to about +2V, this I think lowers the heat produced by the linear regulator a lot, and could easily exceed 300 MHz, using normal K6-2 CXT CPUs, you can start by trying 300 (6X 50), 330 (6X 55), 360 (6X 60), and if at this frequency the temperatures are acceptable, you could try with 400 or even 450 MHz (6X 66 or 75).
AMD 286-16 287-10 4MB HD 45MB VGA 256KB
AMD 386DX-40 Intel 387 8MB HD 81MB VGA 256KB
Cyrix 486DLC-40 IIT387-40 8MB VGA 512KB
AMD 5X86-133 16MB VGA VLB CL5428 2MB and many others
AMD K62+ 550 SOYO 5EMA+ and many others
AST Pentium Pro 200 MHz L2 256KB