As Chopper said, we can't really give a concrete answer without much more information about the size and requirements of your applications. But in general:

• If it's running more-or-less happily today on a 6-year-old WinXP desktop, any modern hardware you throw at it will probably be hugely overspecced.

• I would generally go for larger RAM first, so you can have larger in-memory buffers. If you can keep most of your working set of commonly-accessed data in memory instead of hitting the disc, you're golden.

• A 64-bit-capable CPU is a given in today's mainstream. To use 4GB+ RAM you'll need to install a 64-bit OS on it, but that's not anything out of the ordinary any more.

• Dual-core or quad-core is also a given. You can go higher than that, or multi-CPU if you really want, but for a simple database server you are unlikely to need it.

• If you really want to spend some money, put an SSD in it!

From serverfault bobince

• Hello, I have a 6 years old computer (WinXP) working as MySQL database server.

  Finally decided to invest on a new computer to replace this old one but do not know what do I need to focus to have the best performance.

  What is better processor speed, dual processing, multithreat, high cache memory, 64bits procesor? Or maybe a motherboard with 2 processors.

  I would appreciate your opinions.

  Thanks in Advance

  Jerry

  ChristopheD : Hi, welcome to stackoverflow.com. This site is meant to be the best platform for programming-related questions. This particular question will probably be soon migrated to one of the `sister` sites (serverfault.com or superuser.com). Create an account there and have your answer!

  Chopper3 : There's no way to properly answer this as you've not stated your app load, users, db size, resilience requirements, budget, scaling, response requirements, skill levels, support requirements etc.
  From $pageUsers[$post.author].name

• Well, this depends heavily on the size and workload of the database. If it was running fine on a 6y old desktop machine, everything you get today as server grade hardware will likely fit the bill.

  What do you see as the main reason why you want to replace the current system, except it's age and the fact it's running XP?

  Some fundamentals: Basically, I would focus on lots of main memory and a really fast disk subsystem, as these are the main bottlenecks with databases. CPU speed isn't so much of an issue for moderate or low loaded databases, but 64bit CPU/OS is important, if only to allow more than 4G of RAM.

  Bart Silverstrim : From what you later described, you would need a 64 bit database server to take full advantage of more RAM. But you seem to have an issue because you have 6 years of sales on a server that is running an otherwise small business...I'd think that a better approach might be to archive some of that database out into another table that's not constaly queried, or find a way to optimize that table. I just think it's silly for a small business to run a ginormous server because of one table being full of hardly used data...
  From SvenW

• Depends on what you're doing to the database.

  How hard are you pushing it? You were using a 6 year old system before deciding to trash it...I'm guessing anything you get would be an improvement.

  Without knowing how you're using the computer and what your needs are, you should see something better with just sticking 4+ gig of RAM on it and a fast processor. If you have a gig switch, get a gig network card in the machine.

  Are you using the computer JUST as a database server? If you're doing other things on the system that affects things too.

  And if you're serious about using this thing and pressing it as a server, you already have a backup scheme in place? Or do you need RAID also?

  In my experience if you're doing this at home and not depending on this for income, getting fancy with 16 gig of RAM or hardware RAID or all sorts of bells and whistles will be overkill in the long run. If you ARE using this for income or depend on it being 24/7 reliable, you need to supply your workload, what you're doing with the machine, your budget, etc. and prioritize how you use the machine and what bottlenecks you're seeing now in order to get helpful advice.

  Ernie : Maximum 20 connections at a time? Keep the old server until it releases it Magic Smoke. Schedule it to reboot every night. 20 concurrent connections is nothing, and theoretically speaking, your server should be plenty fast enough for the job until the hard drives fail in about 15 years. If anything, what you have now is tremendous overkill.

  Bart Silverstrim : The real question is, are you experiencing slowdowns with the current server? If so, then you need to find out what the bottleneck is. Processor multithreading, more than 4 gig of memory, useless unless the database software is made to take advantage of it, and from your description you're not pushing it at all, although I don't understand what you mean by "queries to this table make slow process aprox 1 million of registers"? You have 20 connections from 1 million registers?

  Bart Silverstrim : Also...what are you doing for backups? If this hard disk dies tomorrow, are you able to rebuild that server from bare metal restore? If not, FORGET about the (currently working) server being replaced, and get to work on a backup solution FIRST. You need it, ESPECIALLY if you're trying to migrate a business's server to new hardware!

  Bart Silverstrim : Rereading it several times I think I see what you mean by the one table being slow. I think you might want to first find a way to archive some of the table data from a certain period of time and trim the table down a bit, if it has 6 years of sales on it. This is more a problem with your database architecture. For what you're doing, I think you'll stand to gain more if you trim out data you don't use...otherwise, you can throw hardware at it...if you are runnign 64 bit database software, go for a lot of RAM and 10,000 RPM disks. But I think it's overkill.
  From Bart Silverstrim

• Since in a comment you said that you have a table with 1 millon registry, its possible also you need to improve query and not only hardware.

  If i am in your situation, I will buy new hardware if that is possible and also check the slow queries.

  Also I think it would be good idea to avoid windows if you use mysql. Few years ago, I used win2003 with mysql, but when I migrate to linux (host only running mysql service) The performance gain was a lot.

  At respect to hardware (low cost budget): This is like a "home" o "small" setup, for 20 connections. 4gig ram minimum quad AMD (Its a lot for 20 connections at same time,but that computer could run other services also) And of course some RAID setup (you should investigate this) Remember to buy good motherboard.

  If you are going to buy server hardware, I really dont know anything about this...so sorry!

  But, i really think that you have problems with querys!

  At home, i am running a core 2 duo, with 3gig of ram. Its running 20 openvz container with 4 web pages (like 15 connections at same time) and a lot of bots crawling internet (this makes like 1000 querys a second to mysql databases) and I dont have any performance issue.

  Of course, if I had any slow query...well the thing changes a lot about performance.

  Harddrives are sata, not using RAID!

  Of course I am running linux.

  hipe it helps

  From llazzaro