OC for 166MMX

[chrisbviper]

I just want some feed back before i turn this thing on. I had a PMMX @ 166. It was running at 66 bus with multiplier 2.5. Other bus options are 75 & 83.3. I chose the 75 and a multiplier of 5. Will this work right. and if i put it to 83.3 will it hurt it. The manual says that the 83.3 setting is for internal test only and my cause damage, is this a bluff? I'm new to this and don't want to fry anything. Also the voltage is set to 2.8V for the MMX. am i gonna have to change that?

[Tim-]

I don't think that big of jump will work. Try the FSB increase or the multiplier increase. I built a couple of MP3 servers using P166's and they run pretty well at 200 or a little higher, but not much more. Try bringing up the FSB and see how high it will work, then drop it back and try the multiplier and see how high you can go with it. Then try to find a combination of the two that will run stable.

[chrisbviper]

How can I tell if it is stable or not. And what if I put the FSB to 83.3 and multiplier to 5.5. Will that just fry my system?

[DocClock aka MadClocker]

There is no way you can expect 500mhz from a 166mhz chip, it is just too big of a jump..did you even do the mathh to see what you are talking about?
check it out 83.3x5.5=458.15.
at the time the 166mmx came out, the fastest chip was a 200mhz pentium pro... and maybe the D.E.C.Alpha @ 500mhz. if you get 200mhz out of that chip you'd be lucky..a more realistic setting would be to try 2.5x75=187.5mhz, or 3x75=225mhz. 83 mhz is too hard on hard drives..it tends to scramble them real quick. I don't remember what the default volt is for the 166mmx, but I would not push too much at it without extra good cooling, but you might be able to get just a pinch more than 166 owners of yore, as the socket 7/a/370 heatsinks are very good compared to those of the past..so maybe 225 is not so unrealistic but I wouldn't hold my breath.

[SickBoy]

Ok here's my go.....
Like said above, your chip is not going to do more than 233 or so, so basically you shouldnt be shooting the moon here so to speak. From what I hear the non-MMX P200 was the best overclocking Pentium in existence. I have heard people getting MAYBE 300 MHz out of that chip. But you've got the basic idea - step it up in small increments until you max it. Raise the voltage of need be but make sure you have a good cooler, I find a good socket 7 cooler to be the Intel FCPGA coolers that come with a OEM P3 or celemine. I got one from a local computer builder for like $15. Drop a good 60 MM fan on one of those babies and it'll do ya nicely. (like a YS Tech, Sunon or Delta fan) Just dont expect the world from a 166 MMX - certainly not a processor that's going to run games like UT or Q3A no matter what you do to it or what equipment you mate it with.

SickBoy