How-To Geek

Building a New Computer – Part 3: Setting it Up

So you’ve picked out the parts you want, and put the computer together… so now we need to power it on and start setting things up. Sure, you could drop your install cd in the drive, but you’ll have better luck if you check a few BIOS settings and run some tests first, both of which we’ll cover here.

When the computer first powers on, you’ll be prompted to hit a key to enter setup (usually the Delete key). The settings you’ll find in here will be different for each motherboard and BIOS version, so I’ll try to be somewhat general in explaining the available options. When in doubt, open up your manual or ask on our forum.

Setting Up the BIOS Options

Some people might be quick to point out that you can likely install an operating system with the BIOS defaults, but I think it’s best to understand the important options and set them correctly before you do anything else. (Note: If you flash your BIOS to a newer version, the settings will often be wiped and you’ll have to redo them)

The first screen usually lets you set your clock to the correct time, as well as disable the floppy drive (note Legacy Diskette A is disabled below).


The System Information screen will show you the current BIOS version (more on that later), and you can verify that the CPU and memory are detected correctly. If you don’t see the correct numbers here, you need to verify that you installed the memory correctly. (check the manual if necessary)


The SATA Configuration screen has an option that is critically important: Do you want SATA to function as IDE or AHCI?


Here’s what you need to know:

  • AHCI mode allows the computer to use the more advanced SATA functions, and will give you better performance.
  • Windows XP does not natively support SATA mode. You must either create a slip-streamed install disc or use IDE mode here in order to install.
  • Windows Vista or current versions of Linux will function perfectly in AHCI mode.
  • Note: If you install in IDE mode and then want to switch to ACHI mode, you should follow these instructions.

You should also check to make sure your hard drive and CD/DVD drives are detected correctly. This screen will be different depending on your BIOS… in mine it was under AHCI Settings. If the drives aren’t detected correctly, verify that you installed them correctly.


The USB Configuration screen will let you disable/enable USB… the important setting here is that USB mode should be set to use HiSpeed (480Mbps), which is usually the default setting anyway.


There is usually also a screen that will allow you to do a couple of important things… for instance disabling the serial ports or the regular IDE controller. I recommend disabling the ports that you aren’t using, to keep Windows from loading unnecessary drivers for hardware you aren’t using.


The Power Management screen will let you choose the power management options. If you are running Windows Vista, you’ll want to make sure ACPI 2.0 is enabled.


And in the APM Configuration screen you can set a couple more important options:


Here’s what you need to know:

  • If you want to be able to wake the computer from sleep mode using the USB mouse or keyboard, you should enable that option.
  • If you want the computer to restart automatically after a power outage, set the “Restore on AC Power Loss” option.
  • If your BIOS has a “Wake on LAN” function, you should decide whether to enable or disable it… sometimes enabling it will cause the computer to wake up when you aren’t expecting it.

Your motherboard likely has a Hardware Monitor screen, where you can see detailed information about temperatures, voltages, and even the speed of the fan.


The Boot section is also very important: You want to make sure to set the CD/DVD drive as the first boot device so you can easily boot off the installation disc. You could also choose Removable Device here if you want to boot off a USB flash drive.


Note: After you are completely finished installing, you can set the hard drive as the first boot device to speed up boot time.

You can also choose whether you want a quick boot, and whether numlock is on by default. If you are building a computer that won’t have a keyboard attached (like a server), you might want to disable the “Wait For F1 If Error” option, which will allow the computer to boot even if there’s a keyboard error.


Most motherboards will have a System Performance and advanced chipset configuration screens, where you can configure various overclocking scenarios, which we might cover in a future article, but for now you should probably leave everything set to Auto and not really touch those settings.


Finally, there’s usually a section under Security or Boot that will allow you to set a supervisor or user password.


Usually you can set one password to prevent access to the BIOS, and another to prevent booting the system without the password. It’s very important to make sure that if you do use this, you don’t forget the password, because it’s typically a royal pain to reset it.

Note: If there are any other BIOS settings that you feel are important, feel free to mention them in the comments.

Updating Your BIOS

Depending on the hardware you’ve installed in your computer, you might need to upgrade the BIOS on the motherboard before things will work correctly. (For instance, the computer I built last year didn’t properly support the new Core 2 Duo processor until after I flashed it with the latest BIOS version)

In general, it’s best to be running the latest BIOS version, especially if you are buying a motherboard that has been sitting on a shelf for a while. You should check the manufacturer’s website for a new BIOS version (remember where we noticed the version earlier). Make sure to get the right version for your motherboard!

Unfortunately I can’t give you specifics on exactly how to flash the BIOS, since it’s going to be different for each motherboard. It’s very important to check that chapter in your motherboard manual and follow the directions exactly.

Some motherboards might have a flash utility built into the BIOS screen that will let you update the BIOS from a file saved on a flash drive:


Others may have software that you can use from within Windows once you’ve already gotten everything installed:


Still others might require you to boot from a floppy, bootable cd, or usb flash drive, usually running some version of DOS or FreeDOS. If this is the case and you need some help, be sure to leave a post over on our forums.

Important: Make sure you follow the manufacturer’s instructions carefully when updating the BIOS. I’ve not had a bad BIOS update in many, many years… but if it happens the motherboard would probably need to be replaced. The most important thing to prevent problems is to not power the system off during the BIOS update.

Testing the Computer Before Installation

Now that you’ve setup all the BIOS options, it’s a good idea to test the computer to make sure everything is functioning correctly. The last thing you want to do is install Windows and use it for a week, only to find out that you have a bad memory stick causing all sorts of problems.

There are a couple of options for testing… I always use an Ubuntu live cd to test out a computer first, because you can quickly boot and test out the general working operations of the computer:


For instance, within a few minutes after putting the computer together and setting up the BIOS, I was online:


The only problem with using the live cd is that you won’t be testing the hard drive at all… but it’s still a worthy test and it feels great to have your new computer online almost immediately.

Ultimate Boot CD

There are also a number of boot cds which you can download that contain testing tools. If you have a favorite, then be sure to let us know in the comments, otherwise you can always use the Ultimate Boot CD, which contains dozens of testing tools you can use.

Once you boot off the cd, you’ll be nearly instantly prompted with the menu of tools.


If you look under Mainboard Tools, you’ll find the Memory Tests section, where you can choose from a number of memory tests.


I highly recommend at least running a memory test, since RAM problems can be extremely tricky to diagnose later, and can cause everything from corrupted files to complete system crashes. It’s better to know that you have a problem right away than to waste countless hours troubleshooting problems that end up being memory related.


You’ll also find CPU tests and Hard drive tests, although I’ll warn you that most of the generic hard drive tests won’t work for SATA drives. There’s a lot more options to look through if you want.

Note that I’m not necessarily recommending this boot cd over others, it’s just the one that I’m most familiar with. Hopefully our great readers will suggest some good pre-installation testing tools in the comments.

The Best Test

Installing Windows on your computer is the best test of how well everything is running, which is what we’ll cover in the next article. I was originally going to try and cover that here as well, but it really deserves an article by itself.

Stay tuned for the next article!

Lowell Heddings, better known online as the How-To Geek, spends all his free time bringing you fresh geekery on a daily basis. You can follow him on if you'd like.

  • Published 06/8/08

Comments (35)

  1. Rohit

    Good one!

  2. Blue

    Well done! You explained it clearly..

  3. Blue

    what LCD monitor you’re using?

  4. Steve Kalman

    Thanks for a great post. Just a quick how-to comment from a hobbyist photographer. The flash blast on the screen can be avoided if you shoot through a filter. Try the plastic from a take-out container. You can tape the milky plastic part over the flash if you’re using a point and shoot (cut a spatula shape, apply the tape to the handle and use the “blade” over the flash). If you have a pop-up flash, cut the corner of the container so that it just hangs over the flash. You’ll get better family and friends pix this way, too.

  5. The Geek


    Thanks for that… I’m really a terrible photographer =)

  6. Lee Williams

    Just out of curiosity- what was the impetus to disable the floppy drive? Does the BIOS assume you have one, and you didn’t? I know they really are becoming legacy devices, but I have still occasionally found them handy.

    Really liking this walkthrough, BTW. Well done!

  7. Lukychan

    I’m impressed!!!! The Geek…you are a genius :D

  8. rbailin

    @Lee Williams

    Most current motherboards (e.g., Intel 3x and 4x chipset) no longer have a standard floppy connector, so there’s no way to even install a legacy floppy drive. You would think that the BIOS on these mb’s would default to Disabled for the legacy floppy drive, but they don’t always.

    By disabling the legacy floppy, you ensure that it doesn’t appear as a boot device option, and that a USB floppy drive, if connected, will be assigned by Windows as Drive A:.

  9. raju sonbarse

    Really thankful to you.

  10. cuggie

    Greetings, I am really enjoying and learning from this one.
    Thank you

  11. Wil

    I just set my disks to run as AHCI. One of my disks has am IDE to SATA adapter on it though. I should be fine if the system can see the disk, right?

  12. Wil

    Ok, after going here I changed my BIOS settings back to RAID.

    WARNING: Changing the Serial ATA (SATA) mode in the BIOS (for example, switching between ACHI and RAID or between RAID and AHCI) after installing the operating system is not recommended or supported when a SATA hard drive is the boot drive. Switching modes may cause an immediate blue screen with an 0x0000007b error code, followed by a reboot.

    * Serial ATA modes
    * Driver used for each mode
    * Configuring the BIOS

    Serial ATA Modes

    The Serial ATA (SATA) controller has three modes of operation:

    * IDE mode – no AHCI, no RAID
    * SATA mode (sometimes called AHCI mode) – AHCI enabled, no RAID
    * RAID mode – AHCI enabled, RAID enabled

    NOTE: Your system may not have all three options, depending on the motherboard manufacturer and model.

    Driver Used By Each Mode

    The Serial ATA (SATA) mode in the system BIOS determines which operating mode your system is using, whether you need the Intel® Matrix Storage Manager, and which I/O controller you should choose during the F6 installation process.

    IDE mode uses a different driver than SATA and RAID mode.

    * IDE mode uses the native Microsoft* driver and does not require the F6 installation method.
    * SATA and RAID mode both use the Intel® Matrix Storage Manager and require the F6 installation method.

    Configuring the BIOS

    Use the following steps to enable RAID or AHCI mode on an Intel® motherboard.

    To enable RAID:

    1. Enter the BIOS.
    2. Select Advanced.
    3. Select Drive Configuration.
    4. Enable Intel® RAID Technology.
    * If you want to set up your RAID configuration, reboot and press CTRL-I when prompted. This will allow you to enter the Intel® Matrix Storage Manager option ROM user interface, where you can set up your RAID.
    * If you want to make the system RAID Ready, no further action is required.
    5. Save the changes and exit the BIOS.

    To enable AHCI only:

    1. Enter the BIOS.
    2. Select Advanced.
    3. Select Drive Configuration.
    4. Disable Intel® RAID Technology.
    5. Enable SATA AHCI mode.
    6. Save the changes and exit the BIOS.

    NOTE: If you are using a SATA hard drive, the best choice is to set your BIOS to RAID mode and install the operating system using the F6 installation procedure; RAID mode allows your system to be “RAID Ready” and also enables AHCI. This mode provides the greatest overall flexibility and upgradeability.

    This applies to:
    Intel® Matrix Storage Manager

  13. Wil

    By the way I did NOT get the BSOD. It worked fine. I just didn’t want to temp fate.

  14. The Geek


    I probably should have mentioned RAID mode in the article… it’s important to pick the right mode. Keep in mind that many motherboards have different ports for RAID vs regular SATA… not all the SATA ports are automatically RAID-enabled.

    For the majority of people, they will never use RAID and should stick with AHCI mode if possible.

  15. chan

    so your sayin that programs mightont work well if they are out of date and you will need to update them right. do you do that after you got all the hardware installed and window installed. then you download the new updates for bios. and does asus notherboard have a program that lets you update your mother board when done installing windows.

  16. The Geek


    You can update the BIOS at either time, and yes. You might notice a screenshot of it in the article.

  17. Wil

    What I took away from my search was, don’t switch after you install your operating system and that XP doesn’t natively support AHCI.

  18. Serenity

    I strongly encourage users to follow Wil’s advice. I did hang, with a Black screen, then Power Off, and then Blue screened after Power On. During Vista installation F6 isn’t required. What this means is NOT that additional drivers are not required when wanting to use SATA AHCI or RAID advanced features. It simply means you do not have to press F6 to initiate the Add Additional Drivers screen. Vista offers an option of adding drivers without having to press F6 during installation. If you load Windows without additional drivers it gets stuck in IDE Mode. I followed the instructions in the KB922976 article. It directs the builder to enable the msahci driver within registry editor, which you do by changing the start from 4 (diabled) to 0 (enabled), turn Off system, enter bios and change SATA mode from IDE to AHCI. Then, save changes, exit, reboot. This does *not* work. During installation Vista disables all hard disk drivers not in use at time of installation. So, unless additional drivers were offered during installation, you will have to reinstall Windows in order to enable AHCI or RAID Modes.

  19. jay fahey

    Well done! Nice article! Cannot wait to when you discuss OS.

  20. ujangje

    Nice hardworker over here..thx for teaching us step one by one,microsoft also didnt have a good tutorial like this,their xplanations took a long way,n has so many junctions ,at last we can lost our track to reach d end.

  21. Rick

    Has anyone had any problems with drives randomly disappearing when AHCI mode is enabled? Even though all of my drives are SATA, they occasionally aren’t recognized upon boot. If I change the setting back to IDE, there are no problems at all. I’ve searched all over, but can’t seem to find a fix.

  22. Syahid A.

    Superb how to Mr Geek. The Ultimate Boot CD looks like a fantastic troubleshooting tool.

  23. Derek

    This Is What I Have Been Looking For , FOR MONTHS, Thank You Sooo Much, i plan on to build my own computer, i have a good aspect on how to put evreything together but, i dont kno what is next, what i have to do when i turn on my computer, and what do i do in the BIOS menu Thank You SOOOO Much this was VERY VERY VERY VERY VERY Helpfull 10/10

  24. Peter Lowe

    Hey love you web site, intersting information for us beginners. One thing though, your graphics are WAY too large, takes ages to bring up each page.
    Some pictures are 500Kb where 50Kb would be fine. Think of the poor old dial-up users.
    Keep up the good work.

  25. Bryan T. Moore

    I have a question. I just constructed a computer with a 320GB hard drive. Yet, after installing Windows XP, the computer claims that my free space is only about 130 GB! I know that XP does not take up that much room. What gives?

    Bryan T. Moore

  26. Wayne Rayner

    I installed Vista 32 bit on my Asus P5QL Pro and was happy it went well. After reading your install story I tried to change the hdd setting to AHCI and had the problems as Wil stated. Too bad Asus doesn’t explain the choices in the manual. Now to get the performance I paid for I have to reinstall vista. Crap.

  27. Craig Williams

    Will a 10GB HDD hold xp?

  28. Bugaloo

    I plan on putting together a gaming pc or a pc period for the first time. After reading up and looking at the assembly portion of building a computer, I would worry about BIOS portion because I hardly find a post explaining this. Thankfully this turned that all around for me. I will have to return to this post when it comes time for me to put my PC together.

  29. Bugaloo

    Craig Williams

    “Will a 10GB HDD hold xp?”

    It could, but if you are going for patches and updates you would run out of room very quickly. Not to mention after setting it up for the first time it will take a rather big chunk of space just to install the operating system on. My suggestion is; if you can afford something like 100 gb or even 80 go for that instead.

  30. Bubs353

    Thanks you geek!!!! Very detailed and informative. :)

  31. Meteorsurfer

    Thanks for these tutes! These are THE BEST I have ran across! I consider myself an accomplished tech, but by no means a guru and I have sent a few here to answer their own questions (instead of me doing it for them lol!)
    Easy to understand for the beginner with great screen shots to make it even clearer. I especially appreciate the explanations of the “whats, what ifs, and whys” of a step.
    Great job!

  32. James

    I’ve just built a new computer, I’m trying run it with a hard drive from an older computer that already has vista and everything on it but it won’t load, it’s plugged in via sata, when I turn it on it fails to load windows after about a tenth of the loading bar, half a second of some bluescreen shows then it turns off and on and gives me the option of running normally (which does the same thing over again) or running in start up repair mode. I’ve tried unplugging all extras eg graphics card extra HDD but no luck, help?

  33. Trakla

    Great post, thanks a lot how to geek!

  34. Mark

    You’ve eliminated the largest part of the anxiety I had with my first build. Thank you for the clear and useful info.

  35. m_bawitlung

    Great Post!!. Very Useful…Thanks

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