Via Technology has rather spoiled its holiday weekend by releasing a new version of its Mini ITX bios software - because the BIOS version appears to blow motherboards.

Via's own support arena is filling up with complaints from small system builders - big fans of the miniITX board because of what it allows a small OEM to do - all of whom have upgraded to version 1.16 of the BIOS, and found that their board is unable to switch on.

Holiday season absences mean that no comment was available from Via. One source close to the company said: "They are all on holiday in the US, and Taiwan is in bed. It may be Monday before we can get a reply to you."

Builders and experimenters say they have been waiting for several days for any kind of response from the Taiwanese PC giant. "We assume they're working on it," said one, asking for anonymity, "but there's no visible response."

The only advice available is a standard one - and it's one that has raised a few eyebrows. On Via's support pages, there's an article on "How to recover from a major BIOS failure" - but builders say it looks more likely to cause failure, than cure it. The article suggests removing the BIOS chip from a working PC while it is switched on.

"That's about all you can do," admitted Via's John Gatt, Web Media Liaison and technical support engineer, posting on the support forum.

One user - who has complained to Via's European offices in Germany several times in the last week without getting a response - said: "Basically, they want you to go to another good, working PC, and run the BIOS setup utility." Then when you have the config that works, "instead of writing it back to Flash memory, you pull the live BIOS out of your good, working PC, substitute the dead BIOS chip and hit 'SAVE' to re-Flash your dead one," he said.

He added: "I'm pretty experienced at working on system boards, and I wouldn't dare try that. Anyway, I object to the smell of burning flesh... especially my own flesh."

Even the how-to article is starkly gloomy: "If you have some experience, this guide provides information about all of the necessary steps required, but it is to be followed at your own risk and Via accepts no responsibility for any damaged caused."

In any case, say users, even if you feel the risk is worth taking, the fix only works if you have two boards with identical BIOS chips - and a lot of users tend to work on one board at a time.

From the discussion on ViaArena, it is still unclear exactly what the problem is. "We think that if you have changed any of the system defaults, then the upgrade to version 1.16 will kill the board," said one. " It seems from reports that those who set everything back to the default state before upgrading, have succeeded. But we can't get any response from Via."

Another user we approached privately said: "It really should be pulled from their download area, until they have resolved it - or at the very least, they should have a warning in a prominent place that says 'may turn your PC into a doorstep' so that people don't try it blind."

Not all users have reported problems. Several have expressed puzzlement at the debate, saying they've flashed "hundreds" of motherboards. Others say that the problems aren't as severe as a dead motherboard; one says merely that since the upgrade, the PC keeps rebooting, never running more than half an hour without spontaneously re-starting Windows, and often rebooting after just a minute.

The new version of the BIOS has attracted much positive comment, because it updates the display firmware, allowing wide-screen (16:9) format video.

Via has promised to respond as quickly as it can once staff return from holidays.