Memory errors with mi Radeon 9500 :`( help me!!!

[Noedar]

I Bought a new system with my hot new radeon 9500, it worked perfectly like for a month, and then my whole computer started behaving weirdly, it didnt recognized my usb ports (2.0), modem, monitor.
My system is

P4 2.4g
512 DDR266
Gigabyte Motherboard 4Xagp
300 Watts power supply
48x lg cdrw
16x lg dvd rom
80g 7200rpm harddrive
radeon9500pro

I went to the store saying that theri motherboard sucked and they gave me another one ( a shikatronic with almost the same specs of my old gigabyte :s) but they told me the problem was the videocard overheating. And now i cant open any 3d application because they inmediately shut down saying that there was memory reference error. And then my computer stats behaving weirdly again. When i run the 3dmark`03 in the tab of videocard it says my radeon9500pro only has 56megs of AGP memory i dont know if thats ok, also i have it running at 4x with 1.5V of powersupply. Ohh and another werid thing is that in the bios,and startup it says that the systemfan goes like 2400rpm and the CPU fan is always at 0rpm. Im really confused and anyhelp would be really appreciated! i have a kickass hardware i cant even run warcraft3 on the LOWEST settings.....

 

[Zanfib]

What I would do is reinstall everything. Reformat the harddrive, reinstall windows, and get the newest drivers for everything along with Dx9. I found Dx9 helped my system alot with little glitches I had running the Radeon 9500 Pro with Cat 3.1 (Cat 3.0a and up like Dx8 and 9 but I found Dx9 to be more stable). Aside from that I'd open up your case and start the computer up with the case open. See what the fans are doing, and see if the videocard is heating up. By heating up I mean is the GPU fan working and is the heatsink REALLY hot, in my system I have not-too-great cooling but the card seems to run ok. In Bios check your AGP apature settings ATI recommends you set it at the default or at 128Mb. I have no idea what would cause a memory reference error it sounds like bad software (my guess drivers or Dx, I get them while codeing but that's cause I suck and I attempt to write to memory space thats not there.:frown:

Anyways try all that and see what happens, just remember to backup all your savegames and other important files before you start the reformatting.