Can you post the system specs?
Also can you post pictures of that USB + PS/2 card? 😀 I've never seen something like this.

No problemo:
That's my system: Did it... Finally... A High End Socket 370 System

That's the card:

Lazar81 wrote:

Hello. I already have a PCI Card installed in my system. It provides two USB2 Ports and two PS/2 Ports and runs well. I don't need the PS/2 ports. So I searched for a new card that has USB ports at the back and an internal header. I found one manufactured by Lindy. It arrived yesterday and seems to be incompatible with my system. Although it looks like a universal PCI card and usb sticks gets power, the card itself is not recognized or installed. Maybe it works with the Mainboard but isn't compatible with Windows 98. I searched for other cards that are pci2.2 and compatible with Windows 98. They seem to be very rare. Any suggestions?

Which USB controller does it have?

The new one has a VIA VT6212L. The one which is build in momentarily has an NEC chip.

Both the USB controller and the board's chipset are PCI 2.2 specified.
I would rather guess this is due to VIAs shoddy PCI implementation or a defective USB controller card. 😒

What exact chip does that NEC card have? Are those real PS/2 ports or are they using USB on those ports for HIDs that support USB as well as PS/2?

The built-in is NEC D720102 + Chesen CSC0101
About PS/2 I can't tell. I never cared because I don't need them

Lazar81 wrote:

Chesen CSC0101

That's really a PS/2 USB cata converter controller. Nice card! 😀

Under certain circumstances it is

VIA VT6212L is Win98 compatible -- drivers are available for these cards (google "VIA USB 2.0 Host Controller Driver"). I have two of them removed from some PCs I bought and both were working under Win98 in these machines.

Edit: http://download.viatech.com/DownloadDriverSvl?driver_id=2105

Lazar81 wrote:

Maybe it works with the Mainboard but isn't compatible with Windows 98. I searched for other cards that are pci2.2 and compatible with Windows 98. They seem to be very rare. Any suggestions?

There is a Digitus usb controller on offer by Conrad but it does not mention if it has Windows 9x support (which may well be your problem).
https://www.conrad.nl/p/digitus-5-poorten-usb … -20-pci-1909727
You can find photo here:
https://www.digitus.info/en/products/computer … rds/ds-33221-1/
I use a 5-port Q-Teq controller here that works fine on a socket 7 mobo with Windows ME (have not tried Win 98).

Ok. Nice card. But i am searching for one with a usb2 internal header. No internal usb port

Folks... I got it.
I just erased the drivers for the nec controller. Then I put out the card and build in the Lindy card. It works. 😀

https://www.ebay.de/itm/233345837069
Has the NEC chip and at least a single internal USB header.

This one has also just an internal port. No header ... But thanks. The new card is functioning now

Lazar81 wrote:

This one has also just an internal port. No header ... But thanks. The new card is functioning now

Goot thing your card is working now 😀 but I must insist there's a header for a single USB port on the card I posted.

Mea culpa... I oversaw this tiny one...

It is quite simple to replace the header on a cable that plugs into a motherboard with a standard USB plug. I had to customize a standard cable to make it fit with a non-standard SHS frontpanel socket. And you know what ? It's more fun this way 😀. But nice that you got it working.

Lazar81 wrote:

Mea culpa... I oversaw this tiny one...

It's all good. I just didn't want to be the guy that keeps suggesting the wrong kind of card. 😉