My favorite types of thrash border on also being death metal, so Demolition Hammer, early Malevolent Creation, etc
That's also one of my fave mixtures and Ripper do that stuff great.
Some other brutal, deathish young bands off the top of my head:
Exekuter (GRE)
Condition Critical (USA)
Jumalation (FIN)
Contamination (GER)
Excruciator (USA)
Besieged (CAN)
Hellcannon (USA)
Holycide (ESP)
Chemicaust (USA)
Sadistic Ritual (USA)
The Conjuring (ARG)
Torture Squad (BRA)
Kaotik (CAN)
With Malice (CAN)
Invincible Force (CHL)
Entrench (SWE)
For that Havok-Hatchet bit, I just digged out a mix CD I did for myself last year. Title was "Thrash it like Havok!"
Battalion (SUI) - Burried Nation
Savage Messiah (UK) - Enemy Image (Dehumaization)
Legion (USA) - State Of Decay
Space Eater (SRB) - Up On These Shores
Panikk (SLO) - Cruel World (Society To Adapt)
Warpath (UK) - Damnation
Reign Of Fury (UK) - Sorrow Made Flesh
Thraw (SLO )- Injecting Hate
Eruption (SLO) - Fractured
Comaniac (SUI) - 1,2, Rage
Negligence (SLO) - Screaming Fear
Tantara (NOR) - Negligible Souls
Hell's Domain (DEN) - In The Trenches
Sanity's Rage (BEL) - You Are What You Swallow
Aggression (ESP) - Psycho-Crime
Hatchet (USA) - Vanishing Point
From today's point I would add:
Warfect (SWE)
Razormaze (USA)
Shrapnel (UK)
Phrenetix (LIT)
Canceric (CAN)
Mastema (ex-Legion)
Alitor (SRB)