Hi Purec4, and Welcome to the Forum!
The Slot A mobo that's in your HP is pretty limiting, all by itself. Does this look like yours???
The Slot A Athlons only went up to 1 gig, but the chance of finding one of those at a reasonable price today is slim to almost nil.
Here's an example of what I found on E-bay by punching 'AMD Slot A' into the search bar...http://search.ebay.com/AMD-Slo...soke...QQfromZR8QQhtZ1
I only saw two Slot A CPUs faster than your 850, and they're kinda pricey.
The good news is that your Asus K7M motherboard got a very good review on Anandtech back in 1999!http://www.anandtech.com/showdoc.html?i=1079
I think it's time to 'bite-the-bullet' and spring for a newer Socket A mobo.
If you decide to go that way, LMK, and I'll try to help you with your decision.
Here is my new PCChips M848A' ">http://img.photobucket.com/alb...2_T-2-3-3-6-2_M848.jpg v2.1, with a 1700+ @ 2411 MHz, and my trusty old PCChips M810L' ">http://members.lycos.co.uk/mmm...00MHz_Sandra_tests.jpg v7.1A, with a Barton 2500+ @ over 3500+. Some of my fancy cars are on this pag