Not to get into a war with PC VS Mac but my main station at home is a custom built PC.  I learned how to build them about 5 years ago and I follow a few computer forums.  It has proven a learning curve but the reward and price has far out weighed the cost I would have spent.  To date I have built 7 PCs all of which are running AMD/ATI.  I do like the Intel Sandy Bridge but there is no need for me to transfer into that area because I can swap and parts (such as ram or CPUs) around if something went wrong or diagnosis.  

Cost
----
It cost me around 3000 for a really good design station and the specs are:

 - [Antec 900 computer case][1] 110.00 (I chose this for the air flow but dont go less than a mid tower)
 - [Antec 900 watt PSU][2] 130.00 (Nothing less than 550 if you are running separate GPUs)
 - [Asus Motherboard][3] 200.00
 - [Eight Core CPU][4] 160.00 (I would not go less than quad core)
 - [GSkill RAM 32gbs][5] 220.00 (I would not go less than 8gb per the cost of RAM these days)
 - [SSD][6] 250.00 (Note the size of the ssd matters with Adobe.)
 - [2 Workstation GPUs][7] 240.00 (stay with Workstation over Desktop it helps with the graphics)
 - [Backup hdds in RAID 1][8] 180.00 (I love RAID 1 because if one goes down I still have a backup of files)
 - [Monitors][9] 680.00 (just a little overkill)
 - [Quad Monitor stand][10] 90.00 (one of the best stands I have ever owned)

The above you can estimate around 2500.00 USD.  Im sure I can find cheaper if I shopped around and from experience you can watch [Amazon][11], [Newegg][12], and [Tigerirect][13] on prices.  

Now all the above is over time and all the parts come from manufacturers I have used over and over again.  In a few years when motherboards are better I may get another motherboard that holds bigger RAM.  If a 12 core CPU comes out in AM3+ I can swap with the 8 core I have now.  I didn't buy all of these at once they are a collection over time, but as I stated once you start down the custom building path you tend to find a company you like and you can mix and match when needed.  The great thing also about over time I don't have to spend another grand here or another grand here.  I can spend usually 250 every couple years and my system is still running better than whats out there.

NOTE on the ssd.  I first bought a 60ish back in the day during the CS4 master suite and quickly filled that up.  I would suggest not going lower than 128gb.  Also some ask me do I overclock and the answer is no.  

Currently my old stations run as RIP stations/servers all with quad core and 4gbs in a Linux environment.  To date I think I own around 20 HDDs in different RAID configurations. I was lucky a few years back and bought 10 Western Digital 1TB Blacks on Black Friday @ Best Buy before the flood and snagged them all for 39.99 each. 

My point is though Macs are great but when you do your own thing and work on projects at times buying all Macs are not feasible.  Not saying there is anything wrong with a Mac but that's just the facts when money is involved.  

As far as a laptop I still have an old Inspiron 1720 I use as a Ubuntu terminal for PDF processing and to take with me when I need to.  I do plan to buy a mac but I'm still on the debate on whether I can justify the cost for a desktop VS laptop. Also, still use your old laptop and put it to work!



  [1]: http://www.newegg.com/Product/Product.aspx?Item=N82E16811129021
  [2]: http://www.newegg.com/Product/Product.aspx?Item=N82E16817371050
  [3]: http://www.newegg.com/Product/Product.aspx?Item=N82E16813131969
  [4]: http://www.newegg.com/Product/Product.aspx?Item=N82E16819103961
  [5]: http://www.newegg.com/Product/Product.aspx?Item=N82E16820231485
  [6]: http://www.newegg.com/Product/Product.aspx?Item=N82E16820147193
  [7]: http://www.newegg.com/Product/Product.aspx?Item=N82E16814195112
  [8]: http://www.newegg.com/Product/Product.aspx?Item=N82E16822136697
  [9]: http://www.newegg.com/Product/Product.aspx?Item=N82E16824009245
  [10]: http://www.amazon.com/Standing-Monitor-Stand-Widescreen-Displays/dp/B003D7FC8M/ref=sr_1_2?ie=UTF8&qid=1365602018&sr=8-2&keywords=quad%20stand
  [11]: http://www.amazon.com/ref=gno_logo
  [12]: http://www.amazon.com/ref=gno_logo
  [13]: http://www.tigerdirect.com/