The most likely scenario is that this case had a tempered glass window that was shattered. Here is an example of a PC case with a window panel:
The H200 showcases the signature design introduced with the H-Series. The elegant all-steel construction embeds the iconic cable management system that streamlines building and upgrading your system. You can easily build a powerful system with plenty of options for storage and cooling. Includes t...
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Personally, it sounds like this PC was heavily abused by a previous owner. It certainly has some dubious provenance.
It's a shame you have never bothered to post a photo of the unit in question.
Nah, you can run the computer fine without the side panel. Competitive overclockers don't even use cases, everything is laid out on a table or bench so they can easily pour liquid nitrogen, etc. onto the CPU or into their homemade cooling system.
Note that all these PC components are developed and tested in labs without cases. If you look at photos or video of PC component manufacturing labs, all this stuff is laid out on workbenches for easy access. This is not a recent practice. Digital computers have been designed/built like this since at least the Fifties, maybe earlier. You stick it in a box when it is "finished."
In fact, some case manufacturers specifically market open air cases like this one:
Bring out the modder within you. The Core P3 Tempered Glass Edition Open Frame chassis sets a new benchmark in groundbreaking open frame chassis design. With full support for liquid cooling and Thermaltake PCI-e X16 Riser Cable included - the Core P3 is built from the ground up to make even the m...
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This isn't specific to computer cases. There have been cars with exposed engines. Many motorcycles still have a number of exposed part that could easily be shrouded. High-end audiophile amps proudly flaunt exposed components (especially their tubes).
Look at the ISS. There are tons of exposed components and wiring. That's okay because there are only a handful of supremely qualified and careful individuals in proximity.
Stuff like that.
Generally speaking computer cases provide (in no particular order):
- Aesthetics
- Easy handling
- Protection against component damage
- Human safety (so people don't stick their fingers where they're not supposed to like fan blades, hot VRM heatsinks, capacitors, etc.)
- Sound reduction
- Pet safety (if you have any of those)
If you can determine who manufactured the case and the model, you might be able to order a replacement panel from the manufacturer.
Note that an average mid-size tower case might go for $60. They come in all different designs, colors, styles, etc. They aren't just beige boxes like back in the Nineties.
Since the case is already in a partly trashed state, this might be an opportunity for change.