How to upgrade my very old desktop pc?

I have a really old desktop ( i think its a lenovo think centre m52) which originally had vista but I downloaded windows 7 on it and now its really slow. I was thinking all I needed to do was put some RAM and an internal or external hard drive but is that all I need to do to upgrade itproperly (the cheap way) in order to play aproper pPC game on it and to run a daw

I reformatted my desktop, now no sound drivers?

I need download and install the audio driver but it's not on the mfg website. I have tried all obvious options and nothing works. Speakers do work because when I touch the little green plug to the metal, I can hear it in the speakers.
Lenovo 3000 H200 series, Windows XP home, SP2, Legacy audio. Like I said I tried everything, system settings, etc.

Should I get a desktop or laptop?

I have a budget of about $500-600. Things I use the computer for are forums, listening to music, reading and MapleStory. As you can tell, I'm not a gamer.

Do I need two of the same RAMs to operate a desktop?

Do I need two of the same RAMs to operate a desktop? I have a Lenovo H530. 4gigs of RAM obviously. I'm looking to upgrade it but I have little knowledge of it. If I wanted to install one 8gb RAM but leave the second one there. Will my desktop still operate? Is 2 8gig rams necessary or 2 4gig rams? I do video/music production, I'm tired of the waiting time for loading, rendering, etc.

Give me a couple a good gaming Desktops or Gaming Laptops?

For the Desktop max I would spend is 800 because I would need to buy a monitor and for the Laptops I would spend up to 1100 a 13 14 15 inch laptop would be preferred so help! I'm also going to need the laptop for school because I just started Highschool.

Problem with windows 8.1?

So I just got a new laptop a Lenovo flex, and it comes with windows 8.1 upon entering the start screen everything is fine but no icon/app opens, settings etc. The desktop works fine hence me being able to write this but windows 8.1 just won't work i've tried looking through the settings but there's nothing there to help

Is hyperthreading necessary?

Right now I'm torn between the i3 and Xeon version of the Lenovo Thinkserver TS140. I3 has hyperthreading, xeon doesn't. I'm not actually going to be using this as a server, it will be a desktop. Both versions are basically the same price so that isn't a factor.

So, lets amp up the comparison a bit, just to make sure its accurate.

There are two processors. One is an i7 and the other a Xeon E3. Both clock at 3.9Ghz and have an 8MB cache. The difference is that the Xeon is a quad core with no hyperthreading, and the i7 is a dual core with 4 logical cores. Also, the Xeon has slightly better integrated graphics.

Everything else (RAM, PSU, HDD size, etc) is equal.

PS I know this thing has no hard drive, I have my own hard drive.

Added (1). Which is better, our hypothetical i7 or Xeon?