VOGONS


First post, by asaggynoodle

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This seems to be one of my best yet-- I just wanted to know what anyone else thought of it.
This is done on Stock Voltage, with only some minor modifications to the heat sink (Still completely Passive).

CPU:
Intel Pentium PP75 (Non-MMX) Y056.

Overclocks:
75Mhz > 100Mhz (Overclock PLL from 50Mhz > 66Mhz) @ x1.5 Multiplier. [Stable]

100Mhz > 133Mhz (Overclock PLL @ 66Mhz) @ x2.0 Multiplier. [Stable]

133Mhz > 166Mhz (Overclock PLL @ 66Mhz) @ x2.5 Multiplier. [Stable]

166Mhz > 200Mhz (Overclock PLL @ 66Mhz) @ x3.0 Multiplier. [Unstable, no Boot to BIOS, Speaker Static].

I only benchmarked at stock, and current speeds.
SYSBench 4.78 (Stock 75Mhz CPU, 50Mhz PLL):
CPU: 54.87
RAM Bandwidth: 130.10MB/s

SYSBench 4.78 (Overclocked 166Mhz CPU, 66Mhz PLL):
CPU: 120.41
RAM Bandwidth: 173.22MB/s

So, a 222.22% Overclock yielded a 219.44% performance increase (Pretty much Linear Mhz/Perf increase) from stock. Again, no voltage modification.
That's pretty good right? Anyone had a similar experience to this?

Pictures of Bench + Chip:
http://imgur.com/a/rhdN4

Reply 2 of 6, by asaggynoodle

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Good read.

I'm curious to know if my chip is rebadged to satisfy the market demand for the P75 then.. But even for something like a ~P90-P100 these finding are quite a bit above the normal results.

Reply 3 of 6, by jade_angel

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That is an oddly good result. I wonder if it's a rebadged P133?

I didn't know Intel did that at the time, but then, they were often kinda secretive, so who knows?

Main Box: Macbook Pro M2 Max
Alas, I'm down to emulation.

Reply 4 of 6, by asaggynoodle

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That is my current assumption too.
An interesting read talking about the same concept:
http://dfarq.homeip.net/overclocking-pentium-75s/

One thing that really kind of blew me away, was how much better the Disk performance is after the fact. I'm assuming that being the FSB improvement and not the CPU itself.

Still, the one thing that leaves me underwhelmed on the machine is the CT65550.. Slow as balls, Wish I could Overclock that too.

Reply 5 of 6, by jade_angel

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I bet that did speed up the IDE performance. Some of that might be disk cache, too, since the memory is now faster. Also, if the UI goes wonky during disk access, even marginal improvements can make it feel a heck of a lot faster.

Main Box: Macbook Pro M2 Max
Alas, I'm down to emulation.

Reply 6 of 6, by asaggynoodle

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I agree, It looks a lot like on the second graph you see the IDE bus or the Drive itself being the bottleneck at around that ~91MB/s speed.
Where as on the first one I took, it give the impression of being all over the place for whatever reason.