VOGONS


First post, by Sphere478

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what's up!

so I'm starting a wacky socket 7 build using a iWill p55xb2 motherboard

I did some tinkering on this motherboard 16 years ago and this is what I was able to accomplish through jumpers

well i was able to get a 75mhzfsb / 450core out o this mobo heres how […]
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well i was able to get a 75mhzfsb / 450core out o this mobo heres how

what efect the jumpers on a iwill p55xb2 rev1.21 have on a k62+ 550

120=360 core 60.1 fsb
133=400 core 66.8 fsb
150=120 core 48.1 fsb
166=133 core 53.5 fsb
200=200 core 66.8 fsb
c200+=451 core 75.2fsb
233=233 core 66.8 fsb
266=400 core 66.8 fsb
300=133 core 53.5 fsb
t75=451 core 75.2 fsb
rsv=no post (cyrix cpus only i think)
if 83mhz isnt in the 2 i havent tried does any one know of a way i can get to it maby 2 jumppers? ill try thise 2 but i dont think its on them ill keep u guys posted.... well i checked and its a no go only 75mhz butim gonna try combinations of 2 jumpers

this is suposed to enable some features of the k6+ on unsuported mobos
http://www.upgradeability.com/K6plus/utilities.htm

got the linky from repo man11

this time around I think I may be able to use a 10k resistor to specific pins on the clock gen and then to ground to set the unjumperable speeds
i can't seem to find the specific datasheet for this clock gen though. just one for ones with similar part numbers?

help?

Sphere's PCB projects.
-
Sphere’s socket 5/7 cpu collection.
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SUCCESSFUL K6-2+ to K6-3+ Full Cache Enable Mod
-
Tyan S1564S to S1564D single to dual processor conversion (also s1563 and s1562)

Reply 1 of 4, by Horun

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Sorry but fastest clock on a pll52c62-01x is 75Mhz as far as googling many pages, maybe some one will have better luck.
FWIW 83Mhz bus on TX is somewhat doable but also creates lots of other issues. Sure the TX could easily run at 75Mhz AND sometimes run at 83Mhz but was never designed for that.
My P5TX-Bpro r2 runs up to 83Mhz but still has a max 3.5 multiplier AND overclocks the PCI and ISA at 83Mhz. You cannot take a lessor SS7 and make it a full SS7 like a FIC 503+ too many limitations.
Ok just rambling and good luck

Hate posting a reply and then have to edit it because it made no sense 😁 First computer was an IBM 3270 workstation with CGA monitor. Stuff: https://archive.org/details/@horun

Reply 2 of 4, by frudi

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http://www.ryston.cz/petr/mirror/www.phaselin … ts/PDF/6201.pdf

According to this datasheet, there is a setting for asynchronous 83 FSB/32 PCI clock mode. The three frequency selection pins F0-F2 need to be pulled low.

Reply 3 of 4, by Horun

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frudi wrote on 2021-01-14, 07:32:

http://www.ryston.cz/petr/mirror/www.phaselin … ts/PDF/6201.pdf

According to this datasheet, there is a setting for asynchronous 83 FSB/32 PCI clock mode. The three frequency selection pins F0-F2 need to be pulled low.

Good find ! last night found only simple references in chinese(?) that did not translate well.
Did find the original p55xb2 motherboard manual in .DOC format, will convert and add to Vogons Library..

Hate posting a reply and then have to edit it because it made no sense 😁 First computer was an IBM 3270 workstation with CGA monitor. Stuff: https://archive.org/details/@horun

Reply 4 of 4, by Sphere478

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woohoo!!! thanks guys! you all rock!

gonna let you all know what I end up finding when I get the board and have time to play with it

Sphere's PCB projects.
-
Sphere’s socket 5/7 cpu collection.
-
SUCCESSFUL K6-2+ to K6-3+ Full Cache Enable Mod
-
Tyan S1564S to S1564D single to dual processor conversion (also s1563 and s1562)