if not can you tell me what the best graphics card i could get is?
More aboutpossible bottlenecking
well your motherboard has a pcie x16 slot so you are good on that front....the only thing is I cannot find the psu specs for that machine on hp website. can you open your case and find out what wattage your psu is? and a 550ti would be a nice upgrade for that rig.
Well, without even looking at the website, I'm going to say the 550Ti is not going to work.
Besides, there are much much better options than that anyway. You've got an HP, which most likely has a 300W PSU. The most you could run is a HD7750.
But I would much rather recommend a power supply upgrade and a better card. Do you have a budget?
Only stating that there seem to be no 100% guarantee.
Tom's should make a database of known working combinations of mobo/gpu's, would save a lot of hassle.
yea for sure you are right there is no guarantee...but the chances are slim...really there is no guarantee that any computer components will work together perfectly. there is always small isolated instances of certain combinations of parts not working together