Hate to be a bearer of bad news, but installing Win98 on AMD Geode GX/LX-based systems isn't easy, unlike the slightly older NS Geode GX1.
Before thinking of installing Windows 98, make sure your Geode PC has PS/2 connectors for both your keyboard an mouse, without them Windows 98 is pretty much out of the question as far as usability is concerned. Most AMD Geode GX/LX systems don't have them from my observation, at least none of those in my mini PC/thin client collection has one.
Moreover, AMD Geode GX usually comes with CS5535 or CS5536 southbridge chip which doesn't officially support Win98, however there's one particular board which has Win98 driver available: TR2350 (also used in Fujitsu-Siemens Futro A200 series thin client). Someone has covered the board and has kindly provided a link to the driver in the article (http://www.toughdev.com/content/2015/03/explo … le-motherboard/), worth a look IMO. AFAIK Ethernet driver and graphics driver are compatible between AMD Geode GX and LX, not sure about audio.
Also, have a look on Phil's article on the older CS5530 chip: https://www.philscomputerlab.com/cyrix-mediagx-cx5530.html
Some of the drivers for CS5530 may be usable in CS5535/CS5536 too. However, DO NOT install the IDE driver as they'll crash and cause Win98 to not boot properly, I learned the hard way before.