Upgrade from Pentium w/MMX to Cyrix MII troubles

[DonTech]

I am currently trying to solve the problem of upgrading an original Pentium w/MMX to a cyrix MII-300GP. With the Pentium installed, everything works fine as it always had. After installation of the Cyrix (with correct voltage and multiplier settings), the machine starts to freeze about half way through the boot up process. Could anyone be so kind as to offer some possible sollutions? All advice is apreciated.

 

[DonTech]

What OS...and type of motherboard are you useing? Also list your system specs as well as RAM type and how much. Also..since your switching CPU's...boot up with the Pentium...then power down..clear the CMOS via the jumper...then install the Cyrix chip and boot up.

Sorry for omition...I'm using Win98 with a P5TA Ver:F motherboard. 64MB in two DIMM banks. Creative 95' Sound card. A 3Com EtherLink 3 95'. and a Trio display adapter. Pretty old machine really but my instructor charged me with upgrading it. (I am in advanced computer repair training) I will go ahead and try your advice and post an update by tomarrow. Thanks

 

[DonTech]

ok...went through with your advice. It ran perfectly fine again with the Pentium installed. I powered down and cleared the CMOS then installed the Cyrix and restarted. It is still having the problem of freezing up right after windows boot.

I had a class mate tell me to try taking out one of the RAM boards. It is the strangest thing, because it works fine with one or the other RAM board installed but not both..... they are both the same 32MB sticks with nonparity. Leaves me confused...

 

[Shroud]

Hmmm.. that is strange.. it must not like paired SIMMS

 

[DonTech]

I have already been to the manual but I think I have found a different solution. The Cyrix MII-300gp has a L1 cache of 256 bytes and the Pentium 200MHz w/MMX has L1 cache of 16KB. Would that have a major difference when addressing the RAM?

 

[Shroud]

It shouldn't.. just performance difference.. however I guess it could..

 

[DonTech]

Well, I've finally got it figured out! Ok, the 2 SDRAM DIMM sticks I have installed are identical, spec wise. But, they are made by two different manufacturers. (no one has asked me that question yet) It doesn't ake a big difference to a Pentium who makes the RAM, so long as they are the same in spec's. A Cyrix, however, is very picky and wants completely identical RAM sticks to be installed. So, because of their difference in manufacturers, the sticks were incompatible with a CYrix processor. Yeah!! Thanks for all your help, steering me in the right direction.

 

[Shroud]

SO its working now?