Old skool overclocking, P83-OD.

[RoadWarrior]

Just been setting up a system for my wife, an extra one for her. She didn't want it networked, so she didn't get any of the good bits Well she only wants it for text bashing. So I dragged out my boxes of 486 parts and found one of the better boards, pulled out a 83Mhz Pentium overdrive that I got in a box of junk that I never tried, and a VLB ATI Mach 64 ditto, and threw them together with a couple of 400Mb hdds and 32Mb of RAM .....

So, it works and I'm googling up and down the net to find overclocking info for P83 overdrives, and everything I found said not to bother. So of course I did. Bus set to 40, CPU humming along nicely at 100, that's the stuff. Hmm was it stable though? back to the old standbys, looded up doom, ran a few timedemos, nothing flakey there, installed quake, played up to level three, quite playable on default res, felt the CPU, barely even warm! Left it looping the quake demos now to see if it warms up any.

So, I'm thinking either all the OC info on the net about these is BS, after all a lot of really awesome sites have shut down or had clearouts. Or I've got a really sweet chip. A lot of people had trouble on 486 boards though getting the bus above 33, it's not the CPUs it's the boards, so that might have been the reason for the bad o/c rep. This board is really sweet though.

Okay it's not that awesome an o/c'er I had the bus set at 60 for it's first boot (by accident, didn't check the clock) and it didn't want to run at 150 but I think I'll go see how it's doing now, and maybe try the 50Mhz bus on it.

I am not sure whether the cores on these are identical to regular pentium cores, but the version is showing on a diagnostic as stepping c0. Now P75 c0s and P100 c0s have always been incredible oc'ers for me, the 75s going to 125 or better and the 100s hitting 150. So maybe there's more in it yet

Road Warrior

 

[deathstar13]

yeh ive been going threw this with my backup pc.
i want it oced.but it wont.its not the cpu,its the mobo.

if ya get lucky and find a old asus or somthing its almost impossible.altho ive had luck taking my 200mmx out and dropping a p133 is i can oc it. even a [email protected] or so.but the mobos made back then just are so limited!.

currently im looking for new mobo/cpu for my backup.luckily its sdram and atx.

 

[RoadWarrior]

Sometimes you can do PLL chip mods on those, or find undocumented jumper settings for the clock jumpers to get 75 and maybe 83Mhz. Some even have a 108Mhz setting too, but even if you sit your board in the freezer overnight most won't POST on it. I always try every combo out.

This one wouldn't POST on 50Mhz.. Might be the graphics card though because I've never had that one in a system before. I've got a Cirrus logic board that I know runs on a 50 and even 60Mhz overclocked VESA bus but it's not worth the hassle swapping it around because it probably won't be 100% stable like that. It did get quite warm looping quake for a while so it's probably safest to leave it at 100 or I'll be having to recover her documents with a sector editor every few days

For another board etc for your spare take a look at this....
http://www.compgeeks.com/details.asp?invtid=AI61-700128-F-SK
Not really gonna get more upgrades on that, but for what you get now it's a reasonable deal. Probably you'll need a good 250W PSU to run it though, and a 300 if you put 1337 graphics in it, so if you've only got a 200W PSU in that system it may not be worth it. Might hit a Gig if the overclocking Gods are with you.

Road Warrior

 

[Penguin4x4]

Well she only wants it for text bashing.

try out www.tinyapps.org for some 95/3.1 progs. All fit onto a floppy.