What can I do with this PowerPC Mac?

That's a PowerMac G5 you have. They were made from 2003 to 2006. They were pretty powerful for their time. You could still do web browsing on it, I imagine. They'll only be able to support up to OS X 10.5 Leopard, though. You may be able to find out more about them here...
http://www.everymac.com/systems/apple/powermac_g5/index-powermac-g5.html

 

Sounds like you have a dual core 2.3 GHz. Those are very powerful machines. I use a PowerMac G5 as my main Mac, it's faster than my Intel Core 2 Duo. Using the Leopard Market or the PPC Archive, you can download all kinds of great software.

Certainly. It's probably already usable, but if that's a liquid cooled model you may have to check for leaks. I also recommend upgrading the RAM, as 1GB is not enough to get by on today. RAM is pretty cheap; just make sure you buy the right type. This is a useful article about that. After the upgrades, you can use your PowerMac for just about anything.
Thanks for saving the PowerMac from the trash. PowerPC Macs are still very capable and there is no excuse for throwing them away (unless they are broken beyond repair, and even then you can reuse the case). I hope you enjoy your PowerMac!

 

I think it could also be a dual core 2.0 ghz machine. They are all good. It is still very usable. Don't sweat the power cord it's simply a server style cord. Just Google search c19 power cord and you'll find what you need. I've posted some short clips of my 2.0ghz machine, and yes they are still useful computer.

 

There should be a grey sticker underneath the panel with the stock specifications, this should tell you what CPU it has, and whether it is single CPU or dual(-core) CPUs, or even Quad CPU.

 

An SSD would probably help. The graphics card can be upgraded pretty easily, but be sure to get one that's compatible.

 

I know I'm going to ruffle some feathers here, but.... I have found my dc2.0 more competent at browsing the interweb using linux than it was using osx. Also my kernel will actually support an ssd. I know I know, one can be used despite being supported. Also I can use an "unsupported" graphics card (I'm one of a couple using a 4xxx series radeon hd).

 

By that do you mean more compatible or efficient?

 

More able to properly render webpages, and able to do so quicker. Even using tff.

 

Tenfourfox isn't available for Linux, so I assume you mean Firefox? Have you tried Midori or Qupzilla yet? I have found them to be light-years faster on my PowerPC Linux boxes. Your two youtube videos are great, I would love to see what Midori could do on that beast of a Powermac you have. Make sure you get the Midori 0.5.11 from the Debian Sid or Jessie backports, not the stock 0.4.3 Midori in the Ubuntu repos. It's crash-tastically bad.

This guy has Midori and Qupzilla installed, he opens them but doesn't really show performance.

 

Ok here's you max specs:
- RAM: 16GB (I would go with 8)
- SSD: Any size SATA 2 SSD (usually the best for compatibility), or a Samsung Evo 840 (One of the only SATA 3 SSDs reported to work in G5s
- Graphics: Nvidia FX4500 (most vram) or an X1900 XT/GT (fastest) Both would require a power cable, and you could get a Mac card or a PC card to flash

I would definitely recommend running Leopard, you can run Linux, but the PPC version has issues with nVidia cards

 

Honestly, I wouldn't run Linux as a main OS on a PowerPC Mac. Maybe to have fun with it a little bit every now and then, but to get a PowerPC Mac to run just Linux to me seems pointless. You can get any cheap old laptop/desktop and run Linux on that. The entire point of buying a PowerPC Mac is to stay in the older Apple ecosystem. I'm sure some could disagree, but I don't think what I'm saying is totally untrue.

 

Yeah I get the whole older ecosystem thing, but for me it was love of the hardware. It drives me nuts to think that perfectly capable hardware that can still perform well today has been abandoned and dubbed a dead architecture. So I guess in the end regardless what os is being used so long as it is being used is AOK in my book.

Btw, the 16.04 Ubuntu Mate will boot and install fine in your g5 (I'm assuming you have the Nvidia 6600le)