AT ABOUT 0430 PDT, THE NON-INSTRUMENT RATED PLT DEPD CAMERON PARK, CA, ON A FLT TO ELKO, NV, WHERE HE WAS TO RPRT TO WORK BETWEEN 0700 & 0730. WHILE EN ROUTE, THE ACFT CRASHED ON NEARLY LEVEL TERRAIN, NEAR THE BASE OF A MTN, AT AN ELEVATION OF ABOUT 4800'. IMPACT OCCURRED AT DAWN. AN EXAM OF THE WRECKAGE REVEALED THE ACFT CRASHED AT HIGH SPEED, WHILE IN A LEFT WING LOW, NOSE LOW ATTITUDE. A WX STUDY SHOWED CLOUDS EXISTED IN THE AREA FROM 6000' TO 15,000' MSL WITH WX CELLS MOVING FROM SOUTHWEST TO NORTHEAST. APRX 35 MI WEST-SOUTHWEST AT RENO (ELEV 4412'), THE WX WAS (IN PART) 1000' SCATTERED, 3200' OVERCAST, VISIBILITY 8 MI, WIND FROM 290 DEG AT 6 KTS. NO PREIMPACT PART FAILURE OR MALFUNCTION OF THE ACFT OR ENG WAS FOUND. RADAR DATA SHOWED THAT JUST BEFORE IMPACT, THE ACFT'S ALTITUDE VARIED FROM 12,500' TO 8,300' MSL, WITH A DESCENT RATE OF UP TO 2900'/MIN. NO RECORD OF A WX BRIEFING WAS FOUND.