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Wht's the fastest unlocked PII?

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Reply 20 of 32, by The Serpent Rider

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S3, Nvidia, 3Dfx, Matrox, Cirrus Logic, some ATi. In other words, the usual stuff.

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Reply 21 of 32, by RoberMC

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I have an ulocked P-II 450. I just were lucky as there are no precise guidelines to get one, i also was not looking for one, it came in a bundle of parts. The way to overclock them is lowering the multi and upping the fsb, but it does not go much higher than 500 Mhz anyway. A bit pointless generation of CPUs for our purpose IMHO, too fast for DOS, too slow for Win98

Reply 26 of 32, by gerwin

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pentiumspeed wrote on 2020-02-10, 21:23:

Yes what I meant is because I asked two questions, one is missed.
Is there a reason to slow down PII to run SVGA games or need more processing power?

For several DOS SVGA games; more power will help framerate.
See the benchmark table here: 50 to 133MHz FSB on a BX Mainboard

AlessandroB wrote on 2020-02-10, 22:08:

ok, i means the fastest can go at 133Mhz, sorry for my criptic title

Got it. But I suppose that question has been answered pretty well.

In case the system is mainly used at 133MHz, I would use a 300MHz Klamath core. Because of the Deschutes L2 cache behaviour at 2.0x.
Otherwise an unlocked Deschutes 333 or 400MHz would be best. In that case a 333MHz CPU with L2 cache rated for 200MHz (half speed cache) and a modded heatsink would be my personal choice. I consider the unlocked 450MHz model too rare to consider here.

Last edited by gerwin on 2020-02-10, 22:38. Edited 1 time in total.

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Reply 27 of 32, by SpectriaForce

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pixel_workbench wrote on 2020-02-09, 17:27:

the 333mhz version has a higher default multiplier, and because these multipliers are only unlocked downward, it offers more flexibility than the faster models.

j^aws wrote on 2020-02-10, 00:00:

Fastest I've used is an unlocked PII 400 Mhz. It easily clocks to 450 MHz (IIRC, 4.5 multi x 100 FSB).

I'm confused now. Can the multiplier of an unlocked Deschutes really be increased? I thought that these were only overclockable by increasing the FSB.

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Reply 28 of 32, by RoberMC

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SpectriaForce wrote on 2020-02-10, 22:37:
pixel_workbench wrote on 2020-02-09, 17:27:

the 333mhz version has a higher default multiplier, and because these multipliers are only unlocked downward, it offers more flexibility than the faster models.

j^aws wrote on 2020-02-10, 00:00:

Fastest I've used is an unlocked PII 400 Mhz. It easily clocks to 450 MHz (IIRC, 4.5 multi x 100 FSB).

I'm confused now. Can the multiplier of an unlocked Deschutes really be increased? I thought that these were only overclockable by increasing the FSB.

There were some older Klamath with fully unlocked multipler, but unlocked Deschutes were all only "multiplier limited", so no possible multiplier increasing.

Reply 29 of 32, by j^aws

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RoberMC wrote on 2020-02-13, 18:17:
SpectriaForce wrote on 2020-02-10, 22:37:
pixel_workbench wrote on 2020-02-09, 17:27:

the 333mhz version has a higher default multiplier, and because these multipliers are only unlocked downward, it offers more flexibility than the faster models.

j^aws wrote on 2020-02-10, 00:00:

Fastest I've used is an unlocked PII 400 Mhz. It easily clocks to 450 MHz (IIRC, 4.5 multi x 100 FSB).

I'm confused now. Can the multiplier of an unlocked Deschutes really be increased? I thought that these were only overclockable by increasing the FSB.

There were some older Klamath with fully unlocked multipler, but unlocked Deschutes were all only "multiplier limited", so no possible multiplier increasing.

This isn't true for all Deschutes. Below is a Pentium II Deschutes 400 MHz (4 multi x 100 FSB default), clocked at 2x multi to 5x multi (at 2x multi, Speedsys doesn't report the CPU name correctly):

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Sidenote - is there an issue uploading and previewing images on this site? I had to use Imgur to host and link.

Reply 30 of 32, by j^aws

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foil_fresh wrote on 2020-02-07, 12:44:

how low can an unlocked P2 go? 66 x 2 ?

Depends on your boards FSB range : 50x2 is possible, maybe even lower. You can also force write-through L1 cache policy as well, depending on the board. This takes you to fast 486/ Pentium 60 MHz range. And all caches disabled takes you down to 286 range.

Reply 31 of 32, by H3nrik V!

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j^aws wrote on 2020-02-13, 23:10:

This isn't true for all Deschutes. Below is a Pentium II Deschutes 400 MHz (4 multi x 100 FSB default), clocked at 2x multi to 5x multi (at 2x multi, Speedsys doesn't report the CPU name correctly):

Isn't that because Deschutes disables L2 cache at 2x multiplier?

Reply 32 of 32, by j^aws

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H3nrik V! wrote on 2020-02-14, 21:06:
j^aws wrote on 2020-02-13, 23:10:

This isn't true for all Deschutes. Below is a Pentium II Deschutes 400 MHz (4 multi x 100 FSB default), clocked at 2x multi to 5x multi (at 2x multi, Speedsys doesn't report the CPU name correctly):

Isn't that because Deschutes disables L2 cache at 2x multiplier?

Speedsys looks like it's choosing this feature amongst others to identify this CPU. Something more specific like the CPUID, 0641, to represent a PII Deschutes is present in the screenshots for both Speedsys and CPU Identification utility, so this outlier CPU has fooled both of these detection tools.