Why my CD-R 800MB (90min) are recognized as CD-R 700MB (80min)?

CD/DVD/Blu-Ray

Why my CD-R 800MB (90min) are recognized as CD-R 700MB (80min)?

CD-R 90min are not like standard CD-R: capacity reported by Windows is not correct.
To be able to use the full capacity of these CD-R, you need a recorder that allows
the "overburning" and set the burning software to maximize the size of the CD (see procedure for your burning software).