Is the HIV DNA PCR test accurate for early diagnosis?

[sara]

If somebody has unprotected sex with somebody who is infected - and then gets a DNA PCR test 3 weeks after and is negative. Does that mostly mean they are HIV negative? I'm confused because that test is used for "genetic material" of the virus itself. But HIV from semen, isn't genetic.. so how is it looking for the actual virus in your DNA?
Because I tested negative on the PCR.. and it woulld have shown If I had the virus, right?

[danfive]

1st issue: HIV is an RNA virus, the test should be HIV RT-PCR test.
2nd issue: a very early infection, will most likely be a low-titer infection and is easily missed by PCR (or RT-PCR) detection. Good news is that your body may have very few HIV viruses in it (hard to detect) but your immune system will very quickly create lots of antibodies (easy to detect). So you should opt for an antibody (or antigen) based HIV test.

[Camahonda]

^ How about getting HIV DNA PCR test done after 6 months of the "window period"?