New config lags when playing game

[Andrzej]

I have a big problem with my current config. It lags in all my games. It was not so before this config. I always asks me to reboot the PC after their launch. Another thing is that my graphics card is 512MB, but it is detected as 1024GB.

Do you have any suggestions to help me?

I tried disabling anti-virus, firewall, etc but got the same result. I have Windows XP Professional Service Pack 2 on my system.

Specs:

Processor: Intel Pentium 4 CPU 3.20GHz
Motherboard: ASUS P5GC-MX 1333
System BIOS American Megatrends Inc. 0402
RAM: 1GB DIMM DDR2
Hard Disk: STM3250310AS MAXTOR 250GB
Video Adapter: ASUS EAH4670 series (512MB DDR3, 2.00 PCIe x16, PS3.0, VS3.0)

[Steve123]

Which PSU are you having? How powerful (in Watts) is your PSU?

[Andrzej]

I am using ADVANCE ATX-5000 - 480 WATTS (vent.80mm). It is quiet older now, if I am not wrong. Does that affects any way?

[Steve123]

In my opinion your PSU is not at all powerful. Just change it with a good and higher powered PSU.

You can also test your config with CPU-Z.