A "slave"? I don't think that is possible...What you could try is to move some of the parts from the old one onto the new one. What is the speed of the old memory and the new memory? They might be compatible. If they are, you could just move the memory and BAM! have a faster computer instantly.
You could also migrate the hard drives and use the old hard drive as a SLAVE. You'd still be able to use it, probably as a storage drive on the new one. You should make SURE it is slave, so it doesn't boot from the old hard drive.
Well, if you have two monitors, why not use them both at the same time? If you have an "add-on" graphics card you can use them together, and have much more "monitor" real-estate.
If you don't want to do any of that stuff, I'd just put together a network with the two. Get a wireless router pack that comes with a PCI Wireless card. Then you can move the other one to anywhere in the house, mostly, and have a network, share files, share printers, use the internet, etc.
I would like to know if I could use the old computer as a slave wich is a systemax tiger P4 2.66GHZ with winxp home.The new computer is an AMD ATHLON 64 3500 processor with win xp home.1.0GB memory 250GB hard drive.I don,t like that I have two monitors on my desk now please help ?thank you