Computer Restarts in Serial Communication VB6

autocad serial port communication

My computer is Pentium Core 2 Quad with 2.40Ghz. My computer doesn't have Serial Port, so I am using a USB to Serial Converter, I have designed an electronic circuit attach to the serial port, which is dumping values in it @2400,8,n,1 baud rate. I had seen the output on hyperterminal, the circuit is working fine.Now I want my VB program to act like a hyperterminal, to show me the values being sent by my circuit. By the time I execute the program, the system restarts without ever showing any error message.It's annoying me a lot, before writing this Thread, I put back my old computer, Pentium III Compaq Presario 6000. As soon as I plug in the power cord, I heard a Boom in the power supply, I then saw the power supply selector switch into 115V from 230V. I didn't notice as if the power selector was changed from its position, now my working Pentium III power supply is dead now. It had it's own original Serial Port and Parallel Port, so if I run my VB6 program into the older machine with it's own serial port, this won't make my system crash, because I had seen that there are extra USBSerial.DLL files in my P4 computer, which doesn't have Serial port, it's a virtual Serial port, so it's driver might be causing the system to restart. So any suggestion as what should now I do about it. Any idea about it, I have to take out some time for my old computer to see how much damage it had brought to my machine.
Any comments, suggestions are highly appreciated.

automatically printout pc restart

Luckily only Computer Power supply was damaged and no harm was made to processor,RAM,drives,etc. Computer guy checked up all the things and replaced the burnt up power supply with a new one.Now I am succesfully able to run my older system.I run the same program in older computer III Compaq Presario 6000 with built in serial port/parallel port using VB6. I was succesfully able to do the serial communication. But in my other computer Pentium 4 Core 2 Quad, my computer gets restarted. It seems like a strange problem to me.I had to ask one more question related to VB6 is that, it's related to programming issue. I'm dumping Hex values from 00 to FF. But I get around 4 to 5 digit hex using this program in text box.


Please tell me what to do, actually in my circuit, I'm trying to make a real time plot, Analog to Digital conversion is going on my circuit and my microcontroller is dumping Hex values from 00 to FF to the computer serial port and by reading the values in VB6 I want to make the graph.
So first I am doing little exercise on VB6 like,
1)Do simple test on Serial Port
2)Make simple graph techinque
3)I have OCX file which makes graphing easy
4)I will do some test on programming and finally make a real time graph

So I'm going level by level to what I want to acquire in VB6. First test was to dump the values succesfull in it.

I'll try to figure out myself as why I'm getting 4-5 hex digit or more where as I should get 1 or 2 digits only.

I told this story of USB-Serial Cable problem to that computer guy, he has good knowledge in computer troubleshooting, programming experience in Visual Studio, C sharp and do work in Visual Basic 2005 and knows much about AutoCad and teaches Visual Basic in his institue. He told me his story, he told me that he purchased a Laser Printer and showed that to me, which runs on a parallel port, by it's look it seemed to me, as if the printer was Laserjet 6L, his new computer also didn't have parallel port, so he used the converter cable USB to Parallel, he told me that he takes out the printout from the printer, but he said he saw some garbage too in the print out paper. So he said to me, my USB-Parallel cable didn't work well. He further added that I hooked up my printer to my older computer which had parallel port and then printer showed no garbage on printout page and it worked perfectly.
I think the solutions of USB-Serial and USB-Parallel are 3rd party in nature. There drivers aren't 100% compatible and not fully functional.What should now I do, these ports aren't made any longer, they are now history. Is there any way I could still use converters with 100% compatablility, maybe the company of USB-Serial converter isn't good and they manufacture unreliable converter cable and their driver that came along with the cable is also unreliable. Have you ever had this kind of experience. Any suggestions, as what should I do now.