Hi
MSI GeForce GTX750 Ti 2GB Graphics card is not tested on this model. You may refer to below document to check the recommended and supported Graphics card for this unit.
http://h30492.www3.hp.com/hpde/attachments/hpde/Hardware-D/740/1/13880_na.pdf
Before going for the Upgrade, check the power specs required for the Graphics card.
As per unit specification, 6200 pro micro tower has 320W PSU.
I hope that answers your question. 
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