I dont think that leaving the side panel off is really a good option, it lets a lot more dust and debris in which is not good. I'm not sure what SE means either it doesnt seem to state that anywhere, if you don't get that one just make sure you know that a 256MB card is going to perform probably WORSE than a 128MB card at this point because no games are designed to take advantage of that much and 128 will be sufficient for probably the next 5 years or more as they can't put requierments above the standard consumer's computer or they lose a large percentage of sales.