A Pentium 233 MMX would be a good starting point for upgrading that as they are readily available and you can still get them cheap if you look hard enough.

Cool, thank you sliderider; would that fit in a socket 7 Optiplex? I thought the motherboard could only take up to 200

Hmm, perhaps you have TOO MUCH of ram there, the chipset only caches memory up to 64 MB.

http://www.anandtech.com/show/72/4 Some info from Anandtech.

EDIT: Just read that you have already tried 64 MB 😒 I think you can overclock the processor to 200mhz, but i doubt that is going to help too much.

You asked this question a while ago

Query: Dell Optiplex processor?

Dumb question but why would Dell have the board support 128MB Ram, yet the chipset only caches half? I should know this, being a hardware nerd and all! 🤣 worked all day...

@sliderider I did, sorry about that...I totally forgot. Got married in September and completely lost track of that.

Well, the chipset supports 128MB of ram, but only caches 64mb... I really have no idea why is that, perhaps Intel just had some weird brainfart? AFAIK that has nothing to do with Dell, but just Intel engineers going nuts at that point? 😜

I have an Optiplex Gs running with a 75mhz Pentium (No MMX)

Before I got my hands on the 75mhz CPU, the Optiplex was housing a Pentium MMX 233mhz.
It ran just fine, but what I had to do (at least for the 75mhz CPU) was to remove the jumpers that set the clock rate on the motherboard. It only listed 100, 133, 166 and 200.

Hope that helps.

Firstly there IS a significant different in speed if you OC your 166MMX to 200Mhz. Don't believe the doubters! Even a vanilla(non-mmx) 200Mhz pentium 1 outshines the 166MMX by quite a margin in most games, especially 3D titles such as Quake and Tombraider. The extra 33MHZ will also give the voodoo card more room to fly.

I moved to windows 95 gaming back when I had an AMD PR 100 and even this lowly CPU could handle games like Diablo and Firefight without much bother. It absolutely flew in dos games also. I suspect that a 200MMX is pretty much overkill for the vast majority of early DOS games (so you probably see a lot of "error - integer divide by zero"). Games were realeased such as Screamer 2, Carmageddon and Skynet that would make use of a fast CPU like the 200MMX - again these titles are much smoother with 200Mhz than 166Mhz - but you mention windows 98 games ... well by the time windows 98 came around and games were being made for direct 7 etc.. the 200MMX was history and most people had P II's with a voodoo 2 by then. Are you sure the games you're playing dont require something more heavy duty?

As an idea - I would say the latest games that were playable (and enjoyable) on my P200 with 3DFX were Forsaken, Screamer 2, Quake 2 and Carmageddon. If you're thinking of Dungeon Keeper - u need a 233MHZ P2 and a Voodoo 2 to run in glide smoothly.

Hope this helps.

I have Quake 2 and Carmageddon. I'm sure I have Forsaken lying around somewhere, as well as the Descent series (my faves!)

For the games I get the "divide by zero" error from, I usually just stick those on my XP machine and utilize DosBox. I know, I know- shame on me right? 🤣
I do have Dungeon Keeper 2, which I also use on the XP rig as I've got twin Voodoo 2's in that machine. It's the picky games like Final Fantasy, Carmageddon, Shadows of the Empire etc. that I stick on the Win98 machine.

Try to get a Tillamook MMX and a board that supports it. They seem to overclock fantastically well.

They're rated at 1.8v, but run quite happily at 2v, and can clock up quite high.

SquallStrife wrote:

Try to get a Tillamook MMX and a board that supports it. They seem to overclock fantastically well.

They're rated at 1.8v, but run quite happily at 2v, and can clock up quite high.

Problem is, finding a board that supports it 😵

One benefit I stick with the Optiplex MB is all of those ISA slots. Totally filled those up with various, fun midi options. I picked up an Axiom 49-key controller this Christmas and use it in conjunction with the various sound cards. It's now a vintage gaming platform *and* musical instrument. 😎

Of course, I still use the Axiom with more modern VST's on my laptop too.

What is the maximum FSB your mobo can handle? If you can go higher than 66Mhz, be sure your memory sticks are at least PC100 instead of the PC66.

Hi guys, sorry to bug you all about this again. I did end up purchasing a Pentium MMX 233 MhZ chip, socket 7. However, the Optiplex Gs has a hardware jumper that only allows speeds of 133, 166, and 200 MhZ. I had previously tried leaving the jumper off, which made the BIOS default to "compatible" speed (painfully slow!) So now I've stuck the jumper on 200, which runs the new CPU 33 MhZ slower. Is it possible to run it at the full 233, or did I mess up along the way somewhere? 166-200 should be noticeable, but I'd still like to max this system all the way.

Usually the 233 settings on boards that support that speed, are identical to those of the pentium 100.

Markk wrote:

Usually the 233 settings on boards that support that speed, are identical to those of the pentium 100.

So, even if I set the board to 200 MhZ (that's as high as it lets me jumper it,) it wouldn't really matter? In the Bios, depending on how I have the mb jumpers set, it's the numbered speed or "Optimal." Optimal was slower than Forrest Gump doing calculus during the Ice Age, so I set it back up to 200.

I'll run some tests tonight with Windows 98 games and see how she runs. Maybe Jedi Knight and Dungeon Keeper II under Glide mode.

basically on these systems the only way it has to know what to run the cpu is at is with jumpers you set on the motherboard. there is a chance that jumpering multiple sets will get you the desired results, there is also a chance that setting the board to run it as if it were a pentium 100MHz (66 * 1.5) will make it work properly. overclocking in these days was wonderful and with the p166-p233 it was a breeze you just set the speed you wanted and had fun.

Have you considered a Slot1 Pentium 2 machine? Maybe 266MHz? I'm sure you can pick one up for next to nothing. I found that a P2 400MHz, with a 440BX chipset was the perfect all-rounder for me, but that's because I'm a fan of games created between 1990 and 1999.

It's sometimes too fast for the old dos games like Tex Murphy 1&2, but that's what moslo is for.

Also remember, since you're a DOS game fan, any Intel CPU faster than 200MHz opens you up to the Borland Pascal Runtime Error 200 bug, and WinBPFix doesn't always solve the problem. 🙁