AVAST causes system unresponsiveness on Win XP Pro 64bit

I tried the fixes suggested here:

http://forum.avast.com/index.php?topic=98082.msg782047#msg782047

and here:

http://forum.avast.com/index.php?topic=94954.msg756934#msg756934

to no avail.

This is a new install of Win XP Pro 64 SP 2 with all Windows updates except remote desktop installed. No other AntiVirus was installed, Malwarebytes Anti-Malware (free) is installed and Windows Firewall is on. I have tried AVAST on this system with and without nVidia’s firewall installed.

This is an AMD Athlon 64 X2 Dual Core Processor 3600+ 1.91GHz CPU running on a Gigabyte GA-M55SLI-S4 motherboard with one stick of 512 MB DDR2 ram.

Any help would be greatly appreciated.

I have XP Pro, but the 32bit version and have no such unresponsiveness. But I have 2GB of RAM plus a faster processor and I believe the XP 32bit version is less resource hungry than the 64bit version.

Personally I feel that increasing your RAM would help as I think 512MB for 64bit XP is probably a limiting factor.

What version of avast do you have installed, 7.0.1466 being the latest ?
Did you have another avast version installed before this one ?
Has this always been the same since first installing avast ?

It’s so easy to ‘blame’ Avast for everything - this forum is littered by entries like this.
I would agree with the previous poster that 512 Mb memory is grossly under what is truly required, this will barely keep the O/S working let alone any applications!.
I know that someone is going to come back immediately with the old ‘recommended by MS nonsense’ - believe me you need more good quality RAM.