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dont waste $200 or $400 on it

trust me.... it's nubus (not pci) so no usb.... it's scsi not ide so hard drives are not as cheap as you think.... for $400, or even $200 you can pick up a 7600 or something on ebay, add a $20 usb card, throw in a cheaper ide hard drive and whatever else. i know that doesnt give you a great use for the 7100, but the G3 upgrades are not really worth it anymore..... esp if you do not have an otherwise rigged out system.
if you are just looking for an older mac to play with for a few hundred $$s..... you could score and older imac, or look on ebay. check lowendmac.com or everymac.com to figure out what is inside the machine (and how easy/cheap they are to upgrade).
BEWARE OF RAM! a lot of older macs use goofy ram that is so very not cheap. throwing in a fun amount of ram can cost as much as the old mac. even when buying used ram on ebay.
 
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