I see that Si has already told you about more quality labels but I'll add to that and also give some suggestions from a few of those labels:
From True Force/Pain Eletronics go with any of the Liver Mortis material released after "Boss", and anything by Pleasure Fluids and Swollen Korps will be great.
Units/Artists associated with Filth & Violence are all pretty intense and "hateful" but none more so than Snuff and Xenophobic Ejaculation, Pogrom, Mania, Bizarre Uproar, etc come in a close second. Mania also releases a lot of shit on other labels that is fucking quality hate (after all it is the dude from the legendary Taint).
others off the top of my head..Coma Detox, Machismo, Abuse Patterns and Grain Belt (I would add Wince but he is definitely more Noise oriented, but it is structured in a way that it feels very "mid-90's Power Electronics" to me).
P.S. I just noticed that I have interviewed a good number of these projects. Goto my blog (the link in my sig) and read the interviews, read reviews, etc. I give a 100% guarantee that if hippy, goofy, shitty art scum Noise (watch the horrid People Who Do Noise[/b] documentary for great examples of this style) is ever found on my weblog you can give me shit for eternity because that will never happen.