problem is usb communication with PC

Hi,my self tejas pawar.I have working on one project.in which i use ATmega8
controller.There is simple circuit.The circuit is like that,five switches are
connected to port pins of PORTC(pin1 to pin5).I continuously saning these five
keys and according to whenever key press respected leter(A,B,C,D,E) send to hyper
terminal.The connection between controller and PC usb port is made by using one market
purchased kit ( usb to TTL converter kit )in which CP2102 IC is used.Now problem is
that this circuit works properly with PC having configuration like Pentium,I3 processor ,working properly means then my device connected to PC USB port,is not disturbing to other connected devices to other USB port of PC ,devices like scanner,PS2 keyboard But when i connect this device to PC having configuration (celeron processor,1GB of RAM,1.2MHz frequency)the other connected devices(like scanner,PS2 keyboard) to other USB port are not able to connect or not working properly or not detected.why this type of problem arises and what is solution on it?whether problem in driver of kit or PC hardware.

Problem is with USB2TTL adaptor driver. Check in Device Manager to confirm problem with the driver. Download CP2102 driver from its website for the OS you have on Celeron System. Is Celeron is 32 bit or 64 bit? i3 is 64 bit and you might be using 64 bit OS. Download proper driver for the version of OS you have.