AMD was no better, producing a K6, then a K7 Duron and a K7 Thunderbird. Both Intel and AMD also have various clock speed CPUs, faster clocks are assuimed to run faster, of course. Never get the very fastest as you will pay a premium. Wait 3 months and it will be cheaper when something even faster comes out. W98 requires that the motherboard have at least 24 MB of memory.
Memory is cheap and more speeds up the multiprocessing.
If running Satellite SSTV, you will appreciate more memory. Get a reasonable sized Hard Disk. 15 GB will store far more than you will ever use. Programs are getting bigger and bigger as sloppy programmers expand to fit the available space. I have frequent software crashes due to sloppy programming on conflicting programs.