Dear friends Valeska, José Roberto and Fabrício, thanks for all which answered my question. I read the first two comments in same day and decided to take a time to check inside a lot of  computer magazines I still have on hands, before back here and comment about.

Some are english issues of PC World, Dr. Jobs, PC Mag UK, and some are Brazilian issues of same magazines beside the local PC & Cia, PCs , PCs Redes, PCs Extreme, I also checked some interesting website trying to clear the matter, but my focus remained on the english origin material. Fortunatelly or unfortunately I also reviewed what my old Oxford Concise Dic 9th. Ed, and the Webster's Dic. 10th, both in electronic edition, and nothing about plural for both words.

I remember since late days when I came to the computer's world, around 1974, I think;  in all these years, I never read a technical computer matter, in english magazines, where "hardware" and "software" has been presented in plural. Always in singular. So when I read in some news and others local magazines articles which the writers aren't worried with the correct usage of the words, them I worry with the quality of the translations in magazines.

On the other hands, rarely the words "hardware" and "software" are translated into Portuguese in the articles published locally, in the discussions or articles context. All authors always are mentioning hardware and software, or hardwares and softwares.

Here in the EMB Forum, I read an interesting thread about translation of english text to portuguese. But I don't saved them. :-(  In that thread,  the person involved commented that more important is the person translate the word sense and not only the words by itself, doing the necessaries adjustments for the local language.

Thanks and Regards,

Jorge