Hi Spardha I'm not sure that this is the answer to your problem although it seems it may be.
HP Elite 7300/3300/3305 Microtower, HP Pro 3300 Small Form Factor - Password Security and Resetting CMOS.
There are several posts on this issue. so you may find the answere even if this is not the one.
Failing that, if you have not already looked then it may be a good idea to search the forum on "7300 elite password" which was all I did.
good luck
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