I'm a total newb when it comes to hardware and upgrading. Most I've ever done was add memory to my notebook but am ready to give it a shot.
Not my main computer so looking to just make a minimal investment if its worth it-- I have an HP a530n Pavilion hooked up to an LCD that does 720p. It has an Athlon 64 3200+ and an nvidia geforce fx5200 (128mb). Memory is 512 MB (PC2700 DDR SDRAM). Don't know how relevant it is but Motherboard is Asus K8N8X-LA PES (3 PCI, 1 AGP, 2 DDR DIMM, Audio, LAN, IEEE-1394).
I can play video on it but its not smooth- nearly everything over the internet in boxee for example stutters. I can stream video over my network but it stutters too- tho not as much as boxee. Haven't used it much but netflix seems to play pretty well. I don't need blueray or anything great.
Don't know if I can get away with just increasing the memory or overclocking or if I need a new graphics card or CPU. Open to any suggestions and would appreciate specifics as far as parts that will work with this system.
the biggest thing that will help is a better video card and more ram. I had an HP a320n 2.01 ghz for years (seriously it was 6-7 years old making it a dinosaur in computer age) and could do a lot with it's 2 gigs of ram and a 1 gig video card. The issue you run into is that there just aren't that many agp cards out there. I would check out crucial for some cheap ram upgrades (download their tool or look up the computer by model to see what you max out at). Agp is much slower and less efficient than the newer pci-express cards and there just aren't as many out there.
A card like this would improve your video greatly, but you should also realize you are not going to get as great a return for the investment as you would with a newer computer that has newer components that can be upgraded later. I finally did away with my old computer when the psu died and it wasn't worth putting more money into the old box (may it rest in pieces) and got a refurb inspiron 570 mt for under 360 dollars with shipping from cedarpc.com. The on board video is better and more stable than my video with a 1 gb card ever was on the a320n.