Computer Restarting after new PSU and Case

[7_VII_7]

My computer has had a fizzled out PSU. I went to best busy and instead of purchasing a $80 350watt PSU. I bought an ANTEC Case, with a ANTEC 350 Watt power supply. Well I hooked everything up correctly, (trippled checked), and it boots up correctly, and runs in idle mode (no applications running) in windows XP, but when I run a program like FIREFOX, IE, CS:1.6, or TradeStation, it REBOOTS! Not to sure why this does this. But hear are my specs.

MOBO - ABIT KT7A-RAID
MEM - 768mb 133mhz
HD - Maxtor 133/ATA 80gb ULTRA
DVD - Phillips 12x
CD-RW - LG 24X12X24
VIDEO - GeForce 3 64mb
NIC - Netgear
SOUND - SB LIVE

what is going on... PLEASE HELP!! I work through this computer!

 

[Praetor]

Check the voltages for stability?

 

[Kboy]

Sounds to me like it could be a heat problem. Once, when I was being a real MORON on my first PC project, I hooked a computer all up, but forgot the CPU fan. Needless to say, it shut down after about two minutes. If you don't have a couple of good case fans or a CPU fan, check that. Next, I'd make sure your memory BIOS are set up correctly. If you're demanding a higher speed than they can produce, a lot of instability can occur. You might just have to play around with a few things to fix it.