Pentium 233mmx

I have a pentium I 233mmx processor overclocked to 266. I have increased the bus speed to 75mhz. I have an MIG-R540 motherboard, 256meg of PC100 sdram, diamond stealth IIIS540. There is a setting on the board for 83 mhz, however I don't think this is supported since I can't get it to work. Is there a way to increase the clock multiplier of the CPU past 3.5? I would like to get it a little closer to 300mhz if at all possible. All attempts to increase the clock multiplier and bus speed have failed. Any suggestions?
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  1. well the 233 is not multiplier locked for one. However the 233 just isn't very overclockable period. The fact that you got it to 266 is amazing in and of itself, and if I were you I would not expect much ( if any) more out of it. at 83.3 your pci bus is clocked at 41.7 and your video card probably wont work anyways.

    A little bit of knowledge is a dangerous thing!
  2. Well I have a 233 MMX running at 292 MHz (3.5x83 MHz) for 2 years now without a hitch. First of all, it IS multiplier locked, and secondly, it is quite overclockable, as far as Pentium MMx's go... I use the AOpen AP5T which, in 1997, was considered the most stable board at 83 MHz on Tom's Hardware... I have it at 2.9V instead of the regular 2.8, and I have a BIG heatsink with lotsa thermal paste. My case also has two fans for better convection.

    All my periferals can take the 41 MHz PCI speed: Diamond Fire GL Pro Card, El cheapo hard drives from Seagate and Quantum, Pioneer CD Rom, Hercules Voodoo 2 card, Adaptec UW SCSI controller. I have 64 Mb of PC66 RAM that luckily took the 83 MHz without a shudder but I would have put PC100 if it had existed then :-)

    I think all you need is better cooling: a real heatsink (I recommend the golden orb) and thermal paste. I got mine from
  3. Hmmm, you may be right now I think a little more on it been so long since I played with a 233....... At any rate however, The postee already stated that his will not fire at 83.3 that kinda makes this all a moot point. To go out and buy a golden orb for 233 overclocking is a bit excessive don't you think? Heck you can get yourself a k6-2 for that price and whala, 300+.( well yes that does depend on if his board supports the 2.2v)You however are one of the lucky ones if you indeed did get your 233 that high, even you hae to admit that.

    A little bit of knowledge is a dangerous thing!
  4. Good to see the cpu you have is at 266! (or 262 exactly)

    You should be able to run at a 83mhz fsb, but it all depends on the components you use. Your video card is probably what you run into problems with. Please list your system components and maybe we can weed out any bad ones. Your cpu should be okay, as I've seen many of the 233mmx cpu's running at 300+ on super 7 motherboards.

    On a note upgrading to a amd k6-2, I can't find out if your motherboard will support the 2.2v core for a 400, 450, or 500. You can dig a little deeper on the m-tech website. (I checked and I think that's your motherboard manufacturer)
    A k6-2 would run at a 6x multiplier when you set it to the 2x specified on the motherboard. Thus, 66x6=400, 75x6=450, 83x6=500. If in the end your board won't supply the 2.2v core these cpu's require, there are a couple of companies that make a socket 5/7 voltage regulator adaptor that would change the core voltage to 2.2v for the k6-2 cpu. Concept Technologies is one of them, but I think they went under, as I can't find them anymore. I use several of the voltage adaptors they have and they work beautifully. I know powerleap makes the adaptor too, but I can't find any pricing on them. The good thing is the adaptor just sits on your socket 7 and then you plug the cpu into the adaptor. You may have to flash to a different bios for it to work, but it's relatively painless.

    For now, try to weed out your conponents one by one to see which will not work at the 83mhz fsb. If you can run at 292mhz for another 6 to 9 months, you should be able to pick up a 450mhz k6-2 at that time from someone's upgraded system for nothing.

    If your video card is the culprit, try going with anything from the NVidia line. I've found all of thier cards are stable at 83mhz fsb.

  5. I'm not sure I was that lucky. I chose my processor as wisely as I could, based on info availlable on Tom's site as well as others at the time. I EXPECTED it to go to 292 MHz and sure enough it did. A Golden orb is very cheap: mine cost 13 USD, and thermal paste is a few dollars. The whole point is that you can get more processing power for less money if you choose your hardware well.

    My 233 MMX would not even run at 75 MHz with the retail heatsink. Its been doing 292 for 2 years now with my rig. The secret is COOLING. You definetly need a good readiator and thermal paste, and the golden orb has the best performance/price ratio.

    If I was lucky with my 233 at 292, then what am I with my Celeron 533A at 920 MHz????? Saved about 600 USD off the price of a Pentium III 866 several months ago with that. but maybe it was just luck... If you don't try, you'll bever know. Its easy to justify not trying by making yourself believe its hopeless, but you'll never get anywhere like that. Just my two cents.
  6. But you can pick up an amd k6-2 350 for 20-25 bucks. So then which is better, running at 350 and in spec for 20 bucks or getting a golden orb for 12? Even with the golden orb there is still no gurantees the rest of the components will work at 83 fsb. The fact that the computer does not fire at all is a tell tell sign. We know that it is not the mans RAM as for it is pc-100. If it was an overheating problem, the computer would at least fire up, then overheat and crash. As for the fact it does not even post I highly doubt that even the biggest of fans would help. Don't get me wrong, I am all for overclocking. However, I find it all a little amusing when advice is given that in the long run will end up costing more to run at less ie. replacing the vid card, getting a better heat sink et. all. Btw, I am glad to hear you had such success with your celly, however, even at 922 it does not compare to the p3 866 in terms of performance, however cost wise you did well.

    A little bit of knowledge is a dangerous thing!
  7. Good points. Price versus performance. Operating in spec for almost the same as acquiring the means to operate out of spec is indeed something to consider. Then again, there's also that FPU. There's no doubt a Pentium MMX at 300 would beat a K6 300 in that department.

    Ah well, can't have it all. Though we try hard. :)

    The Jolly Wizened Oaf!
  8. I forgot to mention, I've got a Pentium 200MMX going at 250. Pretty nice. Small heatsink, some troubles now and again, just needs a bigger heatsink and fan (I.E. a k6-2 cooler). It's very nice. Unfortunately the board won't clock higher. But then why would it? That's at 83.3 right now anyway.

    83.3 * 3.0 = 250MHz. WOW! I didn't realize I had it up that high. Video card doesn't have any troubles. :)
    A 233 would goto 300! Sweet. Too bad I don't have one laying around.

    The Jolly Wizened Oaf!
  9. I am not so sure that the 233 mmx has a better fpu then the k6-2 series of chips, it only had mmx instructions and not the sse set. You may however be right, it has been awhile since I payed much attention. And yes better cooling would help in your situation. However, bear in mind the postee of this thread's cpu did not fire at 83.3 So I highly doubt a better cooling situation would help at all. He also states in his post that he has a diamond stealth video 540 card. Then another reply states that he should replace that with an nvidia card ( better overclockability). So where does that leave us... hmmmm get a golden orb for 13 bucks, get a new video card for 110 bucks and then maybe he can get his 233 to work at 292? This just seems to strike me as a little extreme.

    btw have you treid setting your cpu at a 1.5 multiplier? the 2oo should see this as a 3.5 but that may have something to do with your board as well.

    A little bit of knowledge is a dangerous thing!
  10. a k6-2 350 should work just fine at 66.6 x 6 =400
    and his board does seem to function fine at 75 mhz fsb so then perhaps a k6-2 450 75 x 6 = 450

    or for really good performance get a k6-3

    all cheaper options than replacing the vid card and a new heat sink

    A little bit of knowledge is a dangerous thing!
  11. Ok...sorry, I have been out since the holiday. To try and alleviate some of the disputes that seem to be going on, here is some more info. The motherboard will do 83mhz FSB......I was able to do this with a Pentium 166mmx with all other components the same. It locked up twice but I chaulked this off as a cooling issue since I was using the standard (wimpee) CPU fan. The video card ran fine also. I have an old 486 CPU screwed into the heatsink of the video card. I tried increasing the voltage also.....didn't work. I know it can be done and I find it a little funny that my 166mmx would do it but not my 233mxx. I do have a new fan for the CPU, but I haven't put in on yet. I will try that. I didn't think that locking the clock multiplier was practiced until the Pentium II (after 300mhz.....or is it 350?). Another little amendment, On the motherboard it says MTI-R540 and on the manual it says MIG-R540. The manufacturer is M Technology Inc. Also if the Pentium I 233mmx IS multipier locked then is there a way around it?
  12. But does your 233 post at all at 83 fsb? If no then you probably have a cpu that just wont do it, while some can it looks like your cant. If it posts then crashs better cooling maybe an option. Also, does your board have higher clock multiplier options that 3.5?

    A little bit of knowledge is a dangerous thing!
  13. The PC won't power up........well, the power comes on with all the lights but no signals. The monitor switches from standby to the green signal light, but nothing comes up. Yes, the board goes 4.0 or 4.5.......can't remember. I don't have it in front of me. The manual shows a setting for 4.0 but for some reason I think it goes to 4.5. Doesn't matter much because even at 66mhz FSB, I can't up the clock multiplier.
  14. I guess you're right, Ncogneto, if his mobo takes 100 MHz FSB, then simply changing the processor is the best solution. Mine, however, was a TX chipset limited to 83 MHz (in those days only the Cyrix processors did more than 66 MHz). In my case a K6 350 would run at... 292 just like the Pentium, and the Pentium MMX has more clout than a K6 at same speed.

    Concerning my Celeron, all the tests I ever did show it to be between a PIII 866 and a PIII 933. For example, in Sisoft Sandra I get 2470 MIPS and 1220 MFLOPS, while a PIII 866 makes 2160 MIPS and 1072 MFLOPS. Just look at Tom's comparison tables and extrapolate to compare them at same speeds.

    The truth of the matter is: your system overclocks well if you chose the components with overclocking in mind. If you're just trying to overclock any old system, chances are one or two components won't take it: in this case there is luck involved, but not in mine :-)

    I still believe it is worth TRYING to overclock, if only to discover the truth behind what everybody is saying. As far as I'm concerned, I have proof that Intel purposefully sells underclocked processors simply to target different market sectors. In my opinion anyone who refuses to overclock offhand is just happy to be fooled. I like to see with my own eyes.
  15. The motherboard won't do 100mhz FSB. It is officially only 75mhz FSB. Getting it to 83mhz FSB would be great but I just can't seem to get it to work. It would be better to overclock the FSB versus the CPU but right now I would like to get it a little closer to 300mhz. I did check and the clock multiplier goes to 4.5 but I can't get it to work past 3.5..........which is the normal clock multiplier. I increase the voltage and that didn't make a difference. I don't think P1's are locked but this sure is acting like it.
  16. Hmm, your best upgrade path may be the ol' K6 like Ncogneto was saying. However, your mobo would have to support the right voltages for that which it probably does not as it doesn't support the right FSB in the first place (K6 350-450 run at 100 MHz FSB). However with a BIOS upgrade it just might, I know my AOpen AP5T does 2.2V now.

    I forgot if the K6s were multiplier locked or not but the 233 MMX sure is, I tried... If your mobo goes to 4.5x and 75 MHz the best you can hope for is 4.5x75=338 MHz with the right K6. Do compare that with buying a new mobo+Duron or Celeron...
  17. Okay. If the chip won't post, don't try to push it to 83mhz fsb. Just go to a K6-2 450 or 500. You can do it now or later. The longer you wait, the cheaper the new processor will be, but the harder it will be to find.

    Go with pricewatch. Cheapest chips around.
  18. Keep in mind any k6-2 over 350 will set a 6x multiplier when you set the board to a 2X multiplier. That way, you can put in a 400, and set 6X66=400. Also, you can do 6X75=450 and 6X83=500.

    Just set the core voltage to 2.2V for a k6-2 and you should be up and running.
  19. The k6's are not mutiplier locked, and as another post said with the ctx core chips (k6-2,3 350 and above), a 2.0 multiplier will be interpreted as a 6! Seeing how your motherboard has 4.0 and 4.5 clock settings I am betting it does have 2.2 volt support. Don't worry, they run just fine at 66.6, 75, or even 83.3. Let me give you a little hint though. Check into a k63-350. Almost all these clock to 400. They kick the **** out of the 2's. I have one running in a old shuttle mobo like yours (66.6 x6) and it has a cpumark99 score of 40.7. My freinds k6-2 500 only gets him a cpumark99 score of 28.2. For comparitive purposes your 233@266 probably gets you around a 15.

    A little bit of knowledge is a dangerous thing!
  20. Well, I got my hands on a K6-3 450mhz(not a plus). It works great. The only problem is my board sucks and I have to run the FSB at 75mhz. The clock mulitplier is set on 2 (6), so it runs at 450mhz. The only problem is it doesn't post at posts at 400. However, all the tests on the CPU through speed tests and directx 8.0 it registers at 451mhz. So I am assuming that it IS running at 450 and that my board just sucks. Everything has been stable for a day and much smoother. Next step would be to get a different motherboard but I am going to get a thunderbird system soon anyway. Thanks for all the advise.
  21. Good luck with you new setup, although I would have recommended that you got a Duron, (Duron 700 for about $60). :)
  22. Glad to hear it at least you added a little life to that old system and it is way better off than a 266 anything. the 400 issue is just the fact your bios was not programmed to id any thing over that rating so it just post its highest known rating. You would be suprised how well this upgrade path works and running at 75 mhz really isn't hurting you as much as you might think (5% loss). the only thing that does hurt is not haveing an agp slot. One last thing, make sure that your write back cache is enabled If not, by downloading a small program that will enable it will increase your performance quite a bit.

    A little bit of knowledge is a dangerous thing!
  23. impressive overcloking. just want to share my experience here. i have a P166 MMX running at 250 (3x83), too bad the high multiplier for the this processor is 3, otherwise it may hit higher freq. i use retail FHS and do a voltage trick. since my mobo support amd cpus, it has high voltage settings. i set the voltage to 3.5v to achive that speed, rinning perfectly stable. 83 FSB didnt give any trouble to my crappy S3 trio 64V+, HD can tolerate that FSB also. before tweaking the voltage this cpu can hit 233 only, looks like the raised voltage unleashed extra processibg power. (btw, it's nice 50% overclocking :)
  24. change the mainboard that support 100mhz FSB and use 100x3 combo. try and let me know. :)

    i did success with 100x2.5 on a Asus P5A-B (ALi chipset) and 83x3 on Asus SP98AGP-x (SiS chipset)

    <font color=orange>What do you think? :wink: </font color=orange>
  25. Well, I got a new motherboard and a k6-III 450 processor. The board is a Soyo (not my first choice, but it was free). It supports many FSB's which include 100, 112, 124. Nothing above 100 FSB will work. The clock multiplier goes to 5.5 but again......nothing above 4.5 will work. The voltage settings on the board are funky in how it was designed. You can't increase by increments. It is labeled by processor. So without some serious guess work I can't change it to 2.5.....or 2.6. In reply to your post, I'm not sure what you are trying to say. I think you were saying..........get a new motherboard. Well, I did and that didn't help. Although there is a significant increase in performance compared to the other board.......even though soyo boards suck.
  26. Here is what I have now.

    AMD K6-III 450
    Soyo 5EMA+ Super 7 MOBO
    384 Meg PC100 Kingston SDRAM
    Hercules Prophet II MX
    WIN98 SE
    6.4 gig HDD
    4 gig HDD
    50X Acer CD-Rom
    56k UsRobotics
    Predator 4D Wave sound card

    It's a good upgrade from the crap I had before.....not the best but I couldn't beat the price. I upgraded the Mobo, Pocessor, and Video card all for $160.00. Not a bad price considering the video card. It is also the retail version.....not OEM so the clock and memory of the video card 175/183 (stock). All the other parts I had already. Being a Network Administrator at a large company has it's percs. Good contacts.
  27. LOL, ok you ae going to have to settle for 450, the k6-3's big weakness is it is not very overclockable at all. The slower ones (350 and 400) have some headroom but the 450 just won;t do a whole lot more. The additional 256 level 2 cache that makes it so much better than the k6-2's is the culprit, it just cant take the higher freq. If I knew you were going to go the new mobo route I would have suggested something all together differnt though. What did you pay for the 450?

    A little bit of knowledge is a dangerous thing!
  28. Well, actually I got the Mobo for free......and the CPU. I "had" to buy a new video card which is SO much better than the last one (Hercules Prophet II MX), and a new ATX case. It cost me about $200.00 for all 4 things. Not bad. I would have prefered to get a Thunderbird CPU but then I would have had to buy a new board and CPU I am a Network Administrator so the perc's are nice. Good contacts and first dibs on hardware they are getting rid of. I should have gone this route a while ago but I wanted to see if there was a way to overclock a Pentium I 233 past 266 on the board that I had. I'm sure with a new board that actually supported 83mhz it would do 290. I can't justify buying a new board for that unless I get my hands on another free board then it will just have to sit for now. It wasn't going to happen so I decided to jump at the mostly free route.
  29. how about keep the proc. as a <b><font color=green>CPU upgrade roadmap</font color=green></b> for your own reference ?! :cool:

    <font color=orange>What do you think? :wink: </font color=orange>
  30. "Then again, there's also that FPU. There's no doubt a Pentium MMX at 300 would beat a K6 300 in that department."

    No way the Pmmx even @ 350 could touch the FPU of a K6/k6-2 The K6 was against the P2. Now a K5 would get its ass kicked.


    AMD for Life!
  31. wrong, the K6 fpu wasn't comparable to the Pentium, much less the PII. it was the integer performance that was good. 3dnow helped alot when supported.
    If the K6 Fpu was comparable to the PII it would still be produced at higher frequencies.
  32. Dammit I've got a multiplier locked pentium mmx running at 3X83 Mhz, it is rock stable, but when I use fdisk or partition magic, it screws the partitions up unless I run it with 75 Mhz bus or lower. A friend of mine has a Pentium MMX running at 200 (default speed), and it is not multiplier locked, once I overclocked it to 233 Mhz, when I didn't even know what overclocking was, now if wonder if he would like to change his processor with mine...
  33. What processor is it? What is the default speed? Why do you need to use partition magic? I would not recomend it. It (most of the time) causes more problems than it's worth. It would work great on a "within spec" PC but when you start to overclock specialty software you are asking for problems no matter what. If the board is too old to support the size hard drive that you have I am surprised that it will run 83mhz FSB. Of course, I don't know what drive you have but it should work unless you are trying to use something larger than an 8 gig drive........depending on the motherboard.
  34. I've got a Pentium 200 Mhz MMX, it is a very good chip, it overclocks to 225 Mhz with default voltage (2.8 V), and... works properly @ 225 with just 2.5 V, so I suppose it is a good sample, but it is multiplier locked and doesn't allow me to choose the x3.5 multiplier. I've got a QDI Titanium IB mobo. It does support 83 Mhz bus via a beta bios update. My HD is a 8.4 GB Seagate, it should work properly because the bios supports drives bigger than 8 GB. The partition issue happens no matter of Ultra DMA being enabled or disabled. Could it be that the PCI IDE controller does not support 41.5 MHz?
  35. When you say that it screws up the partition...what exactly do you mean? The controller may not be able to handle being overclocked. Try setting it to PIO Mode 3 or 4. I would try (maybe even start at 2) 3 first and then work your way up if you don't get any problems. You should be able to disable and enable UDMA and still ajust the PIO Mode. Keep in mind that when you overclock the are overclocking EVERYTHING on the motherboard. This includes the controllers, memory bus, PCI, ISA, and AGP (if you have it)........among other things.
  36. Some people claim (acording to their measurments) that k6-2 have faster fpu. Only that some programs optimised for pentium fpu.
    P.S. My P233-MMX was runing at 262@75 , now it 250@83 (still testing).
    Not hot at all. i also don't have any problems with video.
    I am worrying about sound blaster, some transistors on it is too hot to touch, and sometimes windows saz that soundblaster gone.

    All i can offer you is the truth. Nothing more.
  37. well, that brings us to the same point we have with the P4. If the software isn't optimized for it, it doesn't work as well, whether its stronger or not. I'm sure SSE2 will kick ***, but until it is mainstream, I'm not touchin a P4.
    Anyway, the software will not be optimized for a K6-2 FPU now, nor has it been, so the point is moot anyway.
    now 3dnow is another can of worms...
    btw, me thinks yer blaster is gonna buy the big one... Windows not recognizing it aint a good sign...
  38. the k6 has about 50% the fpu of a p5 (the first pentiums were called p5=586 p6=686=ppro) when the k6-2 came out it had 3d now which is the floating point version of mmx.
    everybody made fun of the software fix for a fpu short comming. odd that no one is laughing that the p4 is doing the same thing! matter of fact the PIII did it (sse) to keep up with the athlon's fpu.
    any way back to the k6.
    it has about a 95% hit rate on branch prediction! most struggle to hit 90%.
    and yes the integer was strong enough to give an equally clocked PII a run for the money.
    the main down fall was that k6 & k6-2 l2 cache was limited to 100mhz.

    who is more foolish...
    the fool, or the fool that takes his advice?
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