overclocking using bus speeds >66 MHz?

All I can really tell you is my personal experience with an Amptron PM7900 motherboard and an Intel P-100 was a positive one. The Amptron supports 75 MHz bus speed. With a cheapo ET4000 based video card I ran Superscapes 3dbench vga benchmark and achieved a mark of 125 frames per second at 60 MHz X 2 (120 MHz processor speed), and a mark of 142.8 frames per second set at 75 MHz X 1.5 (112.5 MHz processor speed). I would imagine most boards with an Intel VX Chipset would perform similarly. I am currently running the same board with a P150 and an ET6000 based video card at 75 MHz X 2.5 (187.5 MHz processor speed) which performs excellent for Nascar 2 as well as most other games. The ET 6000 hits higher scores in games such as Duke3d and Quake when I compared them directly with the Matrox Millenium, and Mystique and S3 Virge based cards as well. It seems to be the fastest card when playing games not written for a specific video card. Hope this is helpful. Good luck. John

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>Hi group! >Having successfully o/c my P90 to P120 (2x60), I keep reading recently >that it seems to be possible to o/c the board itself to 75 MHz or >more. I have several questions about this procedure: >1. How do you do it? :) >Seems as if some ASUS boards have this feature documented, but my FIC >(PT-2000) doesn't. There are, however, three jumpers determining bus >speed. Only three (out of six possible) settings are documented. Could >I succeed by simply trying out the other possible combinations? >2. Is it dangerous? >I know that fiddling with hardware is always a bit risky, but is there >a chance that I kill my board instantly when changing those settings? >Or is it as 'safe' as processor overclocking (i.e. if it doesn't work, >change it back, and no harm done)? >3. Is it worth it? >There's no way my current processor would work as a P150 (2x75). It >refuses to operate as a P133 (and who could blame it, poor little P90 >that it really is... :) Therefore, viable settings could be P112 >(1.5x75) or, maybe (though unlikely), P130 (1.5x87). Provided the >board itself can take those speeds. I guess a P112 (1.5x75) might be >faster graphicswise than a P120 (2x60), but how much faster? >4. Are there resources about this on the 'net? >Thanks in advance! >-- >Wolfgang Preiss \ E-mail copies of replies to this posting are welcome. > \ (Not necessary if you're posting from Europe.) Junk > \ do you care, spammer? If you find opinions express- >Uni des Saarlands \ ed in the above posting, they're probably mine.

Hi group! Having successfully o/c my P90 to P120 (2x60), I keep reading recently that it seems to be possible to o/c the board itself to 75 MHz or more. I have several questions about this procedure: 1. How do you do it? :) Seems as if some ASUS boards have this feature documented, but my FIC (PT-2000) doesn't. There are, however, three jumpers determining bus speed. Only three (out of six possible) settings are documented. Could I succeed by simply trying out the other possible combinations? 2. Is it dangerous? I know that fiddling with hardware is always a bit risky, but is there a chance that I kill my board instantly when changing those settings? Or is it as 'safe' as processor overclocking (i.e. if it doesn't work, change it back, and no harm done)? 3. Is it worth it? There's no way my current processor would work as a P150 (2x75). It refuses to operate as a P133 (and who could blame it, poor little P90 that it really is... :) Therefore, viable settings could be P112 (1.5x75) or, maybe (though unlikely), P130 (1.5x87). Provided the board itself can take those speeds. I guess a P112 (1.5x75) might be faster graphicswise than a P120 (2x60), but how much faster? 4. Are there resources about this on the 'net? Thanks in advance! -- Wolfgang Preiss \ E-mail copies of replies to this posting are welcome. \ (Not necessary if you're posting from Europe.) Junk \ do you care, spammer? If you find opinions express- Uni des Saarlands \ ed in the above posting, they're probably mine.

See: http://sysdoc.pair.com/ More specifically see: http://sysdoc.pair.com/busspeed.html http://sysdoc.pair.com/75mhzbus.html http://sysdoc.pair.com/overclock.html -- Emory University Graduate School of Arts & Sciences The IWCCCARS Project: Q & A Representative Nascar Setups Page: http://userwww.service.emory.edu/~ebusch/

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>Subject: overclocking using bus speeds >66 MHz? >Date: Tue, 07 Jan 1997 13:45:51 GMT >Having successfully o/c my P90 to P120 (2x60), I keep reading recently >that it seems to be possible to o/c the board itself to 75 MHz or >more. I have several questions about this procedure: >There's no way my current processor would work as a P150 (2x75). It >refuses to operate as a P133 (and who could blame it, poor little P90 >that it really is... :) Therefore, viable settings could be P112 >(1.5x75) or, maybe (though unlikely), P130 (1.5x87). Provided the >board itself can take those speeds. I guess a P112 (1.5x75) might be >faster graphicswise than a P120 (2x60), but how much faster?

Have you tried 1.5/66 for a P100 ? surprisingly you may get better graphics performance than a 2.0/60 P120.

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>> 4. Are there resources about this on the 'net? >See: http://sysdoc.pair.com/ >More specifically see: >http://sysdoc.pair.com/busspeed.html >http://sysdoc.pair.com/75mhzbus.html >http://sysdoc.pair.com/overclock.html

Thanks for that info, Eric! Very useful, as usual. The guy who maintains those pages should be a bit more considerate concerning the length of a single page, though. More than 300 KB for a single page (w/o graphics!) is a bit much... And he might keep his snide remarks about german drivers to himself. ;) Nonetheless, those pages contain a lot of important information on overclocking. -- Wolfgang Preiss \ E-mail copies of replies to this posting are welcome. \ (Not necessary if you're posting from Europe.) Junk \ do you care, spammer? If you find opinions express- Uni des Saarlands \ ed in the above posting, they're probably mine.

> Have you tried 1.5/66 for a P100 ? surprisingly you may get better graphics >performance than a 2.0/60 P120. I tried that (first step), and the performance was about equal for both setups. The reason I went for the 120 solution was that changing the multiplier from 1.5 times to 2 times on my board involves only setting (or not setting) one jumper. That way, I could wire the jumper to the turbo switch and change between 90 and 120 without having to open the case. (Well, it's open anyway most of the time, but still, that way is more comfortable and elegant.) The bus speed selection involves three jumpers. -- Wolfgang Preiss \ E-mail copies of replies to this posting are welcome. \ (Not necessary if you're posting from Europe.) Junk \ do you care, spammer? If you find opinions express- Uni des Saarlands \ ed in the above posting, they're probably mine.

BTW, while waiting for my new CPU to arrive tomorrow I'm still using my old Pentium. I get about the same performance as a P133 (66x2) as I do as a P112 (75x1.5). -- Emory University Graduate School of Arts & Sciences The IWCCCARS Project: Q & A Representative Nascar Setups Page: http://userwww.service.emory.edu/~ebusch/

>Having successfully o/c my P90 to P120 (2x60), I keep reading recently >that it seems to be possible to o/c the board itself to 75 MHz or >more. Well, I can inform you that I succeeded! I simply tried out the undocumented jumper combinations and found some intersting ones (all with a 1.5 multiplier): - two combinations in which the machine booted, but failed to produce anything on the display. - one version where I was informed that I have a Pentium CPU running at 25MHz. :) (board clocked to 18 MHz, probably) - another one with P60 (board 40) - The really interesting combination: BIOS display at boot up reports P120, but with a 1.5 multiplier! It has to be seen how stable the computer will run in this configuration, however. And I'm still a bit puzzled about the actual board speed: different benchmark programs give me values between 120.6 and 128 MHz for processor speed. This doesn't sound like the board was running at 75 - rather, it indicates a speed of more than 80... Graphics benchmarks show that the machine is indeed faster now. Is there a benchmark that measures the board speed? Anyway, this is fascinating. Thanks to everyone who responded to my query. -- Wolfgang Preiss \ E-mail copies of replies to this posting are welcome. \ (Not necessary if you're posting from Europe.) Junk \ do you care, spammer? If you find opinions express- Uni des Saarlands \ ed in the above posting, they're probably mine.

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>Subject: Re: overclocking using bus speeds >66 MHz? >Date: Sat, 11 Jan 1997 12:21:29 GMT >>Having successfully o/c my P90 to P120 (2x60), I keep reading recently >>that it seems to be possible to o/c the board itself to 75 MHz or >>more. >Well, I can inform you that I succeeded! >I simply tried out the undocumented jumper combinations and found some >intersting ones (all with a 1.5 multiplier): >Anyway, this is fascinating. Thanks to everyone who responded to my >query.

Very interesting ! I'm using a Intel Plato Premiere/PC2 board with Neptune chipset. It only documents bus speeds of 50/60/66 and for the life of me I can't find any info on changing the multiplier so I'm assuming it doesn't support it. I have overclocked from 90 to 100 by going from 60 to 66 and thought I had reached the limit but it seems there's hope yet. You have inspired me to take the cover of once again.

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> Hi group! > Having successfully o/c my P90 to P120 (2x60), I keep reading recently > that it seems to be possible to o/c the board itself to 75 MHz or > more. I have several questions about this procedure: > 1. How do you do it? :) > Seems as if some ASUS boards have this feature documented, but my FIC > (PT-2000) doesn't. There are, however, three jumpers determining bus > speed. Only three (out of six possible) settings are documented. Could > I succeed by simply trying out the other possible combinations? > 2. Is it dangerous? > I know that fiddling with hardware is always a bit risky, but is there > a chance that I kill my board instantly when changing those settings? > Or is it as 'safe' as processor overclocking (i.e. if it doesn't work, > change it back, and no harm done)? > 3. Is it worth it? > There's no way my current processor would work as a P150 (2x75). It > refuses to operate as a P133 (and who could blame it, poor little P90 > that it really is... :) Therefore, viable settings could be P112 > (1.5x75) or, maybe (though unlikely), P130 (1.5x87). Provided the > board itself can take those speeds. I guess a P112 (1.5x75) might be > faster graphicswise than a P120 (2x60), but how much faster? > 4. Are there resources about this on the 'net? > Thanks in advance! > -- > Wolfgang Preiss \ E-mail copies of replies to this posting are welcome. > \ (Not necessary if you're posting from Europe.) Junk > \ do you care, spammer? If you find opinions express- > Uni des Saarlands \ ed in the above posting, they're probably mine.

Hello: A lot of good info can be obtained in: http://sysdoc.pair.com/cpu.html