Halo gan, Ane mau tanya ane pakai laptop acer v5-431 (celeron) windows bawaanya win 8 udah upgrade ke win 10. Terus kmrn laptop ane bermasalah ane inul pake win 7. Trus tadi ane nyalain ga bsa, ane mau masuk bios tapibga bisa juga. Peringatannya operating system not found. Ane coba pencet F1-F12 ga