RAM is only part of the cost
Overload Mk. I is open in the card details. Read its RAM cost and unmet Hacker requirement on the left, then press Continue.
Why this matters
Cards can require both RAM and a faction, a group such as Hacker or Corpo shown on the card. Overload needs one Hacker card in play on your side. You have four RAM ready, but your Corpo Mainframe does not provide Hacker. Read the unmet requirement in the card details; you will meet it by playing Admin.
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