S4: Ep.44 Salene Discovers that Pride has been playing in The Game
Salene's troubles keep multiplying, as if being City leader wasn't enough. The Mallrats have moved the Hospital to the Mall, after Java had their first one trashed. To replenish their medical supplies they hijacked a Techno supply truck and carried dozens of boxes back to the Mall. Unfortunately, over time, at least 25% of these have gone missing. Salene has also had a pair of favorite earrings stolen. And now Salene faces the prospect that Pride has not kept his promise - to keep off The Game. In her heart she knew as soon as Patch showed her the picture copied from CityNet. Salene goes to their room and searches through Pride's stuff, and finds the damning evidence in his bag. Lex quietly comes in behind her; he knew where she was going, and what she would find.
Lex   Gaming chips. The thing about Reality Space Obsession—
Salene   Don't say anything, Lex. Please just don't say anything
Lex   You can't ignore it Sal. Who's leading who? Pride or May?
Goof: No Lex, they aren't gaming chips, these are the medicines that have been going missing from their hospital stockpile. Pride would then have sold them, but not for gaming chips, because the computers at the Casino work on swipecard Credits, that look like credit cards. [OK, there's also problems with that one, but go with me here].
So it looks like the scriptwriter, David Fox, put down the formula:
Casino + Pride + Gaming Addiction = Evidence for Salene to find
and came up with Gaming Chips.

Alternative explanation:
It's just possible that Lex is being very metaphorical here. Of course they aren't real Gaming Chips, but they do the same job in that they keep Pride in The Game, because he can sell them for Game credits. Shorthand, they're Gaming Chips. I don't buy that one. Here's why. Before long, Lex and Salene search the City for Jay but find Pride instead. He's already found Jay (and nearly wasted him in his Game-crazed mental state). The shock of suddenly realizing what he was doing has jolted his mind back to some degree of sanity. Lex leaves the two together, and Pride can tell from Salene's gaze that she knows everything.
Pride   Salene, are you OK?... You know...
Salene   I found the Gaming Chips, Pride. Where are my earrings? Please don't tell me you've sold them.... ..Why? Stealing from me when I'm the only one who stood up for you?
Pride   It's worse than that, Sal. I nearly took out Jay. I don't know what's real any more.
So, no mention of medicines, just earrings. Gaming Chips and earrings. It should be medicines and earrings. And I don't somehow think Salene is being metaphorical about the Gaming Chips. Just a goof in the script....
Someone with some sense at Cloud9 decided it was much more appropriate for Salene to find the medicines we know Pride has been stealing, rather than gaming chips which are USELESS for use in computer games. But no one thought to change the script.