The important compatibility is with the Big Chip on board. If it is the same as another recommended card, your slightly different card should work just fine. It may have different interfaces.

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The amount of RAM on these cards adds a little speedup under certain conditions, because if there is enough RAM, the next screen can be drawn into 'off-screen' RAM, and then made active, which allows it to 'snap' into view. I don't think any well-known graphics card is 'starved' for RAM in a way that would really slow it down.

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