This might be a stupid question but anyway. I have the 545 its the mid tower I'm wanting to upgrade my video card to one of the following HD 5670, or 5750 I know the PSU will need upgraded my Question is some of these cards need 2 slots 1 for the card PCIEx16 and the second for the fan/cooler. will this fit it the 545 since it needs 2 slots.
They will fit if you do not have any cards directly below it in the PCIe x1 slot. Most people don't. If you only have one PCI card, then move it down to the lower PCI slot #20 also. Slot #24 is where your video card would go. Slot #23 is your PCI x1. Also, take into consideration any issues with the length of the card. A long card could possibly cover up your top two SATA connectors on the board right below the battery (#9). I don't think this would happen with the 5670 or 5750, but it is always good to take a measurement inside your case so you know what your are dealing with before ordering the video card.
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