How much memory and storage does this desktop come with?

It comes with 16 GB DDR5 memory (1 x 16 GB) running up to 4800 MT/s and a 512 GB M.2 PCIe NVMe SSD.

What processor does the Dell Pro Slim Essential QVS1260 Desktop use, and what is its maximum speed?

It uses an Intel Core i5-14500 vPro processor with 14 cores and can boost up to 5.0 GHz.

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Dell Pro Slim Essential QVS1260 Desktop - Intel Core i5-14500 - 16GB - 512GB SSD - Windows 11 Pro - Intel UHD Graphics 730 - Wi-Fi - BT - WH33F