CYRIX MII-300GP/ BIOS CHECKSUM ERROR

[Neal]

I am trying to boot up a cyrex MII-300GP that I moved from another machine. I am getting BIOS ROM checksum error, detecting floppy drive A media
Drive A error. System Halt

Any advice would be greatly appreciated.

Thank You,

Neal

[Sterling_Aug]

A BIOS checksum error usually means a bad battery. The other errors seem like they are occuring because the BIOS defaults have been loaded because the battery is dead.

[Neal]

Thanks Sterling have a good day.

[Neal]

I am having problems with new chip I moved from one machine to another. Jumper Settings are correct per users manual.

When I try to boot I get BIOS ROM Checksum error
reading device A media error.
System halt.

I removed the battery to replace and see if that was the cause. When I rebooted I lost all video on video card mounted on mother board. I installed another one that I knew worked in PCI slot. I tested monitor on another computer and monitor works fine. I am not sure what I reset but I would greatly appreciate any help anyone may offer.

Thank You,


Neal

[EdT]

Try resetting the CMOS, usually a jumper that you have to momentarly touch. Removing the battery u have to wait at least 20 minutes before all residue power is gone. That should work as the MB is now in default mode, otherwise their something wrong withtyour setting for your CPU. Remember Cyrix CPUs are PR rated so the settings are not as per its performance ratings.

[Rugor]

You haven't mentioned which motherboard you are using or what the actual speed of the processor is. Cyrix marketed at least two different chips at different clock speeds as the MII 300.

One quirk of those processors was that they used non-standard FSB speeds of 75 or 83MHz, which forced the PCI bus out of spec. Not all motherboards and peripherals can function at a 37.5MHz or 41.5MHz PCI rate.

I won't guarantee it, but that might be the problem.

[Peter M]

75 and 83 MHz CPU bus does _not_ necessarily mean out-of-spec PCI bus. In, fact, this only happens on Intel chipsets, and some rare VIA ones. All others that were common at the time, ALi, SiS, and most VIA chipsets did it right.

MII-300 was made in two flavors: 66 MHz 3.5x (suits any chipset) and 75 MHz 3.0x.

Make sure the jumpers match the unit you have, also make sure the board's CPU voltage is set right, and finally think about whether or not the board's CPU voltage regulators are strong enough to feed that processor. Those 2.9V MIIs from the days when IBM made them draw a lot of juice, about as much as a K6/233 did.

regards, Peter