Deionisers remove the dust and scent particles from air, removing the staic lets them drop from the air, stops them floating. So they DO clean air, does'nt do much for your carpet though
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PS, they look quite good (if they work) my house job only has two 'pins' on it and is crap. The one we had before kicked ass though (and was small), you could smell the air like a storm was brewing. Good idea to have one in the
room your rigs in, would stop dust ingesting into the PC PSU but putting a good deioniser in your PC would be pointless IMO, I doubt it'd 'de~static' the entire PC & PSU :shrug: ...