In system properties, click on display adapters. It should show you which card you have. System information on start up will show it as well. Knowing the make without a number to go with it may not help unless it uses a driver from Microsoft.
You can still use the Win98 scan and update feature from Microsoft, you just have to search the Microsoft site to find it as Windows update no longer work's from your computers direct link. I used it last week & downloaded one small update. I don't think the date on it was new, but it hadn't shown up in scans before.