Nvidia FX 5500 UNCLAIMED in Xubuntu 18.04

I have a pretty old system (HP t617m with pentium 4 2.6 ghz) that Im trying to revive using Xubuntu 18.04 32-bit. In order to do so, I bought recently a Nvidia FX 5500 PCI (I have no AGP ports), which I never be able to make it work. I know that are a free driver called nouveau, and I want to use it. In order to use a PCI video card, I set in BIOS the change between onboard and pci graphics. When I make the change, the card gives the HP boot screen normal, but after that it just becomes a black screen. Then Im force to set again the onboard graphics, and everything is normal.

The lshw -C display shows:

 *-display description: Display controller product: 82845G/GL[Brookdale-G]/GE Chipset Integrated Graphics Device vendor: Intel Corporation physical id: 2 bus info: pci@0000:00:02.0 version: 03 width: 32 bits clock: 33MHz capabilities: pm bus_master cap_list rom configuration: driver=i915 latency=0 resources: irq:16 memory:e0000000-e7ffffff memory:ef000000-ef07ffff memory:c0000-dffff *-display UNCLAIMED description: VGA compatible controller product: NV34 [GeForce FX 5500] vendor: NVIDIA Corporation physical id: b bus info: pci@0000:01:0b.0 version: a1 width: 32 bits clock: 66MHz capabilities: pm vga_controller cap_list configuration: latency=32 maxlatency=1 mingnt=5 resources: memory:ed000000-edffffff memory:d0000000-dfffffff memory:ec080000-ec09ffff

lspci | grep VGA shows:

00:02.0 VGA compatible controller: Intel Corporation 82845G/GL[Brookdale-G]/GE Chipset Integrated Graphics Device (rev 03)
01:0b.0 VGA compatible controller: NVIDIA Corporation NV34 [GeForce FX 5500] (rev a1)

lsmod | grep nouveau and ubuntu-drivers devices shows nothing

What I have tried:

-Fresh install, even using different distros -> Always appears UNCLAIMED in lspci -Install nouveau using apt-get install firmware-nouveau -> same problem

Thank you in advance

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