(This FAQ item is periodically updated, due to the ever-new revelations of what havoc VIA chipsets can wreak on their owners).
If your computer's mother board is based on the VIA chipset, you may need to download and install the VIA 4-in-1 drivers. This has resolved a lot of reported cases of computer crashes, locks and freezes, sound card trouble, as well as significantly improved many computer's performance.
Before you download the VIA 4-in-1 drivers, however, Spitfire says that there's a BIOS setting that, if needs to be changed, might resolve your problem without going any further. Make sure that the BIOS "DRAM Clock" value is set to "HCLK" and not to "HCLK + PCICLK". Essentially what this does is to lower you RAM's clock speed to 100mhz. Just remember to set it back to what it should be once you're done installing or updating OFP.
If that doesn't help, before you go on, be aware that installing the VIA 4-in-1 drivers may cause conflicts with your computer's BIOS version, potentially resulting in unpredictable errors.
Sounds confusing? It is. Read on.
Motherboards using VIA133 chipsets and its variants have been known to cause errors when transferring data between two IDE devices (such as between a CD and a hard disk, e.g., when installing software). The transfer error can often lead to corrupted data when transferring large files. OFP's installation involves some large files. What a coincidence!
Though this problem is not specific to OFP, it is easily discernable during the installation of OFP's upgrade patches, since OFP's patch installation procedures check the integrity of the files already on your hard disk before they are updated to a newer version.
If you have a VIA chipset based motherboard and OFP has
displayed CRC/checksum error messages for large OFP files (such as DATA.PBO, 1985.PBO, MUSIC.PBO
and more) while installing an upgrade or an addon patch, this may very well be
the source of your problem.
Here are some BIS and VIA FAQ links discussing this problem:
BIS Troubleshooting FAQ - AGP 4x problem on VIA
Alive! - VIA
686B Southbridge Data Corruption article and links
Elsewhere, the FAQ previously stated that disabling DMA mode for both your CD drive and hard drive may fix this problem. However, this leads to slower performance on your PC and may leads to several other problems on certain ABIT motherboards, such as sounds crackling and popping. If you've disabled DMA before installing or upgrading OFP, try enabling DMA again when you're ready to play.
Some VIA FAQs state that installing both the VIA 4-in-1 drivers and the latest BIOS version resolves this problem. However, some motherboard manufacturers have fixed the problem on their own by releasing an updated BIOS. If such a corrected BIOS version is used in conjunction with the corrected VIA 4-in-1 drivers, the data corruption problem may persist and, worse, may cause additional problems.
To summarize the above, you should install either a BIOS version that corrects the problem or install the fixed VIA 4-in-1 drivers but usually not both.
As an example, Spitfire, the OFP player who first publicized this information, decided to install the new VIA 4-in-1 drivers and to downgrade his ABIT KT7A motherboard's BIOS to an older version (because his CPU runs 10 degrees cooler with the older BIOS version). Since then, he has installed OFP several times and no longer encounters corrupted file errors.
ADDED October 14, 2002:
VIA chipset owners who have through all of the above and still have CTDs and freezes, might want to look into the PCI latency patch for VIA chipsets (this link will display Google search results for the patch). This helped OFP reg Amarak resolve his problems.
ADDED November 5, 2002
A lot of the issues mentioned above and some additional information are documented in this BIS troubleshooting FAQ item.
ADDED June 11, 2002
OFP player Piotr says that, from his experience, Windows 98 users may have better success installing version 4.35 of Via's 4-in-1 drivers. Later driver versions may not be optimized for Windows 98.