If you are looking for HFT trading an EA is not what you are looking for. I have a few EA's running on dedicated hardware in order to conduct fast computations using CUDA, however that is nowhere near close to HFT.
Basically for that kind of work you require FCGPA or possibly even the algorithm implemented in ASIC in addition to infrastructure co-located on exchange premises to ensure low latency. Needless to say this is for institutional clients and not common amongst the users of this page although a few of us may have work related experience in this area.
Should you require HFT to make money, I believe you have already lost.
Just my 2 cents of course...