Learn Hardcore Turkish: Program dondu, bu yüzden bilgisayarı yeniden başlattım. - The program froze, so I restarted the computer.

dondu is simple past (-DI) 3rd person singular of donmak (to freeze). Formation: stem don- + past suffix -du (vowel harmony picks -u after the back rounded vowel o). It expresses a definite, completed past. Compare: donmuş (evidential/hearsay) and donuyordu (past continuous).

Why is there a comma before bu yüzden, and could I punctuate it differently?

bu yüzden (“therefore/that’s why”) introduces a result clause. You can write:

Program dondu, bu yüzden...
Program dondu. Bu yüzden...
Program dondu; bu yüzden... All are fine; a full stop is slightly clearer.

What’s the difference between bu yüzden and çünkü?

bu yüzden = “so/therefore,” introduces the result.
çünkü = “because,” introduces the reason. You can flip the order:
Result after cause: Program dondu, bu yüzden bilgisayarı yeniden başlattım.
Cause after result: Bilgisayarı yeniden başlattım çünkü program dondu.

Can I replace bu yüzden with other connectors?

Yes, with register nuances:

o yüzden (very common, informal/neutral)
bu nedenle / bu sebeple (more formal)
dolayısıyla (formal/written)

Why is it bilgisayarı (with -ı)? Is that the accusative?

Yes. -ı/i/u/ü marks a definite direct object. You restarted a specific computer, so bilgisayarı. Leaving it bare (bilgisayar) would suggest non-specific or would sound ungrammatical here.

Could bilgisayarı also mean “his/her computer”? How do we tell?

It can. bilgisayar-ı is ambiguous between:

accusative: “the computer”
3rd-person possessive: “his/her computer” Context disambiguates. To force possession: onun bilgisayarını yeniden başlattım. To say “my computer”: bilgisayarımı....

Why is the subject “I” missing?

Turkish drops subject pronouns because person/number are on the verb. başlattım ends with -m (1st sg past), so “I” is understood. Ben is added only for emphasis/contrast.

Why başlattım and not başladım?

başlamak = to begin (intransitive): Bilgisayar yeniden başladı (“The computer started again.”).
başlatmak = to start something (transitive, causative): Bilgisayarı yeniden başlattım (“I restarted the computer.”).

What’s inside başlattım morphologically?

stem: başlat- (causative of başla-)
past: -tı (vowel harmony; the -d- of -DI devoices to -t after a voiceless consonant)
1sg: -m Hence the double t: başlat
- tı → başlattı
  - m → başlattım.

Where can I put the adverb yeniden? Is the order fixed?

Neutral is before the verb: Bilgisayarı yeniden başlattım. You can move it for emphasis:

Yeniden bilgisayarı başlattım. (focus on “again”)
Bilgisayarı tekrar başlattım. (using tekrar instead) Turkish allows flexibility, but the neutral spot is right before the verb.

Difference among yeniden, tekrar, and gene/bir daha?

yeniden: “anew/afresh”; the standard tech collocation is yeniden başlatmak (“to restart”).
tekrar: “again” (very common in speech): tekrar başlattım.
gene (colloquial) / bir daha (“one more time”): also “again.” All work here; yeniden başlatmak is the canonical UI term.

Could I say Program takıldı/kilitlendi/çöktü instead of dondu?

Yes, with nuances:

dondu: froze; UI unresponsive.
takıldı: got stuck/lagged (often temporary).
kilitlendi: locked up (stopped responding).
çöktü: crashed (app/process terminated).

Is bu yüzden one word or two? How is it different from yüzünden?

bu yüzden is two words meaning “therefore/that’s why.”
-yüzünden is a postposition meaning “because of” that takes a noun: program yüzünden (“because of the program”). They are not interchangeable.

Can I rephrase with a “when”-clause like “when it froze”?

Yes: Program donunca bilgisayarı yeniden başlattım. Here -ınca/-ince forms a temporal “when” clause.

Could I split it into two sentences?

Yes: Program dondu. Bu yüzden bilgisayarı yeniden başlattım. This is very natural in writing and speech.