Dimension 4600, what GPU do I have?

Dimension 4600 is an ancient AGP based system.

Most modern versions of linux no longer support these cards.

I would not try anything Higher than Ubuntu 12.04.5 LTS or Knoppix 7

http://puppylinux.org/wikka/Wary

Puppy Linux Lupu 5.2.8 would also work.

Puppy 5.2.8.005 standard

The Green Card has a Dell Part number on it.

Typical card is Geforce FX 5200 AGP  part number 9Y452 Dell Nvidia Geforce FX 5200 128MB.

9Y452 AGP

You seem to be ignoring the part about ACESS DENIED REQUEST DENIED.  Ubuntu does not support this chipset or hardware anymore. Nor does MIcrosoft support windows 8 or 10 on this system.

This system is 13 to 15 years old.  Newer versions of linux do not support this.

There is support for Ubuntu but it is not free and systems after that many years are end of life end of support for most vendors.

VGA compatible controller: NVIDIA Corporation NV34 [GeForce FX 5200] (rev a1) (prog-if 00 [VGA controller])
	Flags: bus master, 66MHz, medium devsel, latency 32, IRQ 10
	Memory at e4000000 (32-bit, non-prefetchable) [size=16M]
	Memory at d0000000 (32-bit, prefetchable) [size=256M]
	[virtual] Expansion ROM at e5000000 [disabled] [size=128K]
	Capabilities: [60] Power Management version 2
	Capabilities: [44] AGP version 2.0

  This is not a 64 bit card its 32 bit.

/tmp/selfgz21230/NVIDIA-Linux-x86-173.14.39-pkg1/usr/src/nv/nvacpi.c:265:51:
   error: dereferencing pointer to incomplete type
            status = acpi_remove_notify_handler(device->handle, ACPI_DEVICE_NOT
   IFY, nv_acpi_event);
                                                      ^
   cc1: some warnings being treated as errors
   make[4]: *** [/tmp/selfgz21230/NVIDIA-Linux-x86-173.14.39-pkg1/usr/src/nv/nv
   acpi.o] Error 1
   make[3]: *** [_module_/tmp/selfgz21230/NVIDIA-Linux-x86-173.14.39-pkg1/usr/s
   rc/nv] Error 2
   make[2]: *** [sub-make] Error 2
   NVIDIA: left KBUILD.
   nvidia.ko failed to build!
   make[1]: *** [module] Error 1
   make: *** [module] Error 2

 AGP hasn't been viable for many years and the last version of card that was supported was Radeon 4XXX series with AGP to PCI-E bridge.  Those cards require 400W power supply that is also no longer made as well as Legacy Drivers that are not carried forward.  

The OLDEST machine that is still viable would be OPTIPLEX GX620 with Pentium D 915 cpu.  Newer models like the 745 755 760 780 790 would also be fine. (These systems will run MSDOS thru Windows 10. The main reason is that all of these systems will Dual Boot XP and Ubuntu with WUBI.   You need the XP in order to do bios updates.

The other issue with systems older than the 790 is that there will be no microcode updates for Meltdown and Spectre. 

• The issue is not specific to any one vendor and takes advantage of techniques commonly used in most of the modern processor architectures. This means that a large range of products are affected from desktops and laptops to servers and storage, even smartphones.
• Mitigations include updates to both system software (Operating System (OS) patch) and firmware (BIOS, microcode updates). In some environments this may include hypervisor patches, patches to virtualization software, browsers and JavaScript engines.
• Good security hygiene should continue to be used. This includes ensuring devices are updated with the latest patches, employing anti-virus updates and advanced threat protection solutions.  
• As Intel reported in their FAQ, researchers demonstrated a proof of concept. That said, Dell is not aware of any exploits to date.

• Intel
• AMD