actually the PC now shuts off in the middle of the night. It restarts ok and runs fine after that but I leave it on to get overnight currency data which i can only get live.
Unfortunately many virus and trojans (at least those that are well scripted) run in a "stealth" mode that will not show up in the task manager.
Although this is a popular notion, you neglect to understand that you don't need to surf the internet nor must you open an email attachment to get infected. Hooking up to a modem, which you must do in order to trade, is in itself enough to become susceptible to scanner attacks and other malicious threats like LSASS vulnerabilities. Even if you have a dedicated computer solely for trading, it's still a good idea to install antivirus and firewall.
My dell with windows vista shuts down too. It did that when I first bought it then the problem went away. I reinstalled vista this weekend and now it turns off again. On Monday and Tuesday about 2 minutes before the market opened it went blank. Thank god it didn't do it today.
mine is also a dell with Vista, is there a setting somewhere that does this. It didnt do it before the virus attack.
Cascading two or more NAT routers would offer more security, but unless the trading terminal is completely segregated from other peer machines on the network, it's still hack-prone.