question about MMX

[Special K]

If I have a motherboard that supports up to a P200 non-MMX, can I put a 200 MMX processor in it and run it as a regular p200? Or is there something else (such as voltage) that would prevent me from doing this?

 

[Dark4ng3l]

Yea I beleve they changed voltage specs with the mmx cpu's.

 

[pm]

Probably not. There's a voltage difference between the Pentium 200 and the Pentium 200 w/ MMX tech. If your motherboard does not claim to support the Pentium w/ MMX (AKA P55C) then it almost certainly will not work.

OTOH, there are several other alternatives. Evergreen sells a variety of upgrade processors which should work in your motherboard. Winchip sells upgrade processors which should work in your motherboard. Cyrix might have something that would work. Possibly AMD K6 CPU's might work and you might want to look into this. I think your socket is called "Socket 5", and most of these want "Socket 7", but my memory starts to get foggy on these subjects, so I encourage you to look further into this.

Evergreen's products are usually a little steep for what they are (CPU's with a voltage converter built on), but they are a very good possibility for you.

Edit:

It's unusual for me, the AT Forum's unofficial Intel representative, to steer you towards an AMD product, but I would definitely consider the Spectra 400 for $130 at their page here. This should work in your motherboard (although run their prequal program on your computer to be sure), and should offer you the equivalent performance of a K6-400 for $130 without requiring any changes except for the possibility of a BIOS upgrade.

I have no personal experience with Evergreen's products, but I have heard good things about them from other people.

 

[jsbush]

Nope you can't do it! I've tried it!

 

[xtreme2k]

sory guys

P200 NON-MMX requires a SINGLE 3.3voltage
P200 MMX requires a SPLIT 3.3/2.7voltage <- this requires 2 voltage regulators on the motherboard.

 

[pm]

Right. We all agree that SpecialK probably has a socket 5 motherboard and that the 3.3V voltage plane of the socket 5 (P54CS) motherboard won't support the split voltage plane required by a socket 7 part.

So, assuming you are right, SpecialK, and you have a socket 5 motherboard, you either need:

1. a new motherboard, or
2. an upgrade processor which supports socket 5 natively (Winchip makes these, I believe)
3. an upgrade processor which has a voltage converter built-in (like those made by Evergreen)

 

[xtreme2k]

I dont think this is a socket5/7 problems

I think socket 5 wont take in P166 or above anyway due to the higher ampere requirement

A fair amount of socket7 mobos supports P200 but without a 2nd voltage regulator therefore cannot cope with a P/MMX

 

[pm]

Yeah, you are right, xtreme2k, socket 5 goes from 75MHz Pentiums to 133MHz Pentiums. Socket 7 comes in three flavors, unified voltage plane, split voltage plane, and with extra multiplier pins (and AGP).

This is an excellent document on the subject that covers what chips work in what board. It should answer all of SpecialK's questions and it fixed up my memory on the subject. I found while trying to figure out if xtreme2k was right about me being wrong about socket 5/7.

 

[Whitedog]

I have a plain vanilla P200 P54C I'll trade ya

I have a VX mobo I can use dat P55C in. No wait! That mobo toasted.. neway, I still gots dat P54C if youz wants it. I gives it to you for free E-mail me your address and I'll put it in a small box and stick a dozen stamps on it and throw it in a mailbox. I have a GOB of stamps I need to use up since they won't be worth crap come Jan 1st. (no, I'm not buying 1cent friggin stamps! :|

You might get it before Christmas.

 

[dawks]

Theres really no performance difference between the two chips, so dont worry too much about it. If thats the only reason to swap chips.

 

[Whitedog]

Ya think? uhmmm, yes there is. let's see..
double the L1 cache size (from 8k+8k to 16k+16k)
MMX = most software supports this.
hmmm, actually about 20-30% faster..

I think he just needs a chip he can use in his old mobo (probably 430HX)

 

[xtreme2k]

I forgot but as far as I know the P/MMX does have even MORE enhancement over the P54C than just the larger L1 cache and the MMX unit

I think it has a better branch predictor and a slightly different pipeline

 

[Special K]

Thanks for the info everyone. The motherboard is an Intel TE430VX (socket 7). Because I am planning to get a new system sometime next spring, I am a little hesitant to spend $140 now on that evergreen chip. Someone in FS was selling a P233MMX + mobo, and I was considering that as a possibility, but then I wondered if the RAM in my system would work in that motherboard. It is PC66, 2-clock (whatever that means) CL2, 10ns SDRAM, and seems to be much more expensive than regular SDRAM.