You are building a high-end dual-monitor gaming setup that should last you through years of heavy gaming, streaming, and work. When you buy quality gear once, you avoid the trap of replacing cheap parts every eighteen months.
Timing this purchase during back to school sales means you catch retailers clearing out older stock. Last year's monitor models often drop in price while offering ninety percent of the performance of the brand-new releases.
Keep in mind that 0% for 18 months on purchases and balance transfers from date of account opening is a deadline, not free money. If you still have a balance left when that window ends, the remaining amount gets hit with standard interest.