Help me upgrade old server?

[Jbax1899]

Two years ago I found an old IBM xseries server chilling at a Goodwill (thrift) store. Off an on I've been working on getting it up and running, chugging in this, taking out that. Just today I got it to work, and is right now (at the time of me writing) downloading Ubuntu. Can't tell you how ecstatic I am to have finally got it working, even if it is a piece of crap in today's world. But, thats beside the point. Now I want to upgrade it!

 

Here are the original specs

Here's what I changed (more accurately, what made it work):

• No HDD, disc or floppy drives
• A 5-USB hub expansion through PCI
• A thumb drive I used to download Ubuntu, and a thumb drive I downloaded Ubuntu onto
• 2x1gb of ECC ram, PC3200. I can fit in another two pieces before I hit the system limit of 4gb.

Question is, what can I do now? Obviously add more RAM, but what else? Upgrade the PCU maybe?

 

-Jbax