Mióta ilyen lassú a feltöltési sebesség?

Since when has the upload speed been this slow?

Breakdown of Mióta ilyen lassú a feltöltési sebesség?

• az: the
• lassú: slow
• mióta: since when
• ilyen: such; this kind of

Questions & Answers about Mióta ilyen lassú a feltöltési sebesség?

What does mióta mean exactly?

Mióta literally means since when, but in many contexts it is also naturally understood as how long has ... been ...?

So:

• Mióta ilyen lassú a feltöltési sebesség?
  = Since when is the upload speed this slow?
• In natural English, this may also be expressed as
  How long has the upload speed been this slow?

Hungarian often uses mióta for a state or action that started in the past and is still true now.

A typical answer might be:

• Tegnap óta. = Since yesterday.
• Két napja. = For two days.

Why is there no word for is in the sentence?

Because Hungarian usually leaves out the verb van (is) in the present tense, third person singular, when the sentence is of the type X is Y.

So:

• A feltöltési sebesség lassú. = The upload speed is slow.

There is no spoken or written van here.

This omission happens very often in Hungarian:

• A ház nagy. = The house is big.
• Ő orvos. = He/She is a doctor.

But in other persons or tenses, the verb appears:

• Én lassú vagyok. = I am slow.
• A sebesség lassú volt. = The speed was slow.

So in your sentence, the hidden structure is basically:

• Mióta [van] ilyen lassú a feltöltési sebesség?

What does mean here?