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Form Factors

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ATX was designed to address three major shortcomings of the earlier AT form factor, and it offers a few minor improvements as well. First, a designated portion of the board for the CPU socket keeps it out of the way of long cards, where AT boards had the CPU mounted behind or in place of card slots. Second, the inclusion of a port panel on the motherboard itself negates the need for slot brackets to break out such common items as USB, eSATA, or audio ports. Third, a cooling path from the lower front to the upper rear of the case vents hot air through the power supply and/or an exhaust fan. All three major improvements are centered on splitting the board between the slot and CPU area.

Most significant among the minor improvements was the addition of power-on through the motherboard. This allowed the system to turn itself off at shutdown and made possible such features as wake-on-ring (using a modem), wake-on-LAN (using a network adapter), timed power up/power down, and keyboard power-on hot-buttons.

ATX derivatives are based on the same CPU section, so that smaller boards are able to fit into larger cases if desired. ATX standards include microATX and FlexATX. Most Shuttle-style PC cubes (often called SFF for Shuttle Form Factor or Small Form Factor) use a two-slot variation of the FlexATX form factor reduced to approximately eight inches (later standardized by AMD as the exactly 8" DTX form factor), and VIA further shortened its mini-ITX form factor to 6.75" by reducing the maximum slot count to one. ATX size specifications are based on fractional inches.

The image above compares the maximum size and maximum number of slots allowed on various ATX-based form factors, with dashed lines indicating how the mounting holes in smaller boards still align with those of larger cases.

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shiroikaze 02/11/2010 5:19 AM
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micky_lund 02/11/2010 5:30 AM
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-2+

ahh...the p55a-ud4p..great board

quantumrand 02/11/2010 5:31 AM
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-15+

Top choices for motherboards right now: Gigabyte, Asus, and MSI. Gigabyte is really the way to go, but there are a few Asus and MSI configs that you might prefer.

one-shot 02/11/2010 6:08 AM
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quantumrand :
Top choices for motherboards right now: Gigabyte, Asus, and MSI. Gigabyte is really the way to go, but there are a few Asus and MSI configs that you might prefer.



What about EVGA?

tacoslave 02/11/2010 6:11 AM
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quantumrand :
Top choices for motherboards right now: Gigabyte, Asus, and MSI. Gigabyte is really the way to go, but there are a few Asus and MSI configs that you might prefer.



ah yes i got a got a msi 790fx gd70 with a combo from newegg (phenom II 955)and i absolutly love it. The best part is the overclocking utilities
you can overclock fuckin everything in 5 min or less. Then i got another motherboard from zotac for 60 bucks (before rebate) and it died on me in less than a month and i'm still waiting on a rebate.

Crashman 02/11/2010 7:01 AM
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one-shot :
What about EVGA?



I'll let you in on a little secret: EVGA motherboards are a pain to overclock. Since that's EVGA's market, it's kind of a big deal. As an inexperienced manufacturer they're learning quickly, so hopefully we'll see the kinks worked out pretty soon.

porksmuggler 02/11/2010 7:15 AM
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-7+

Great article for beginners. A quick browse through newegg, and I've built with every brand except EVGA, ZOTAC, and XFX (EVGA and XFX for graphics cards though). I've consistently gone with ASUS for my own and Gigabyte for customers when at all possible. I prefer ASUS for the best overall quality and Gigabyte usually provides the best value. I'm seeing a lot of comments for MSI lately, though I've never put them in the same league.

skora 02/11/2010 7:32 AM
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This is a great reference article Crash. Lots of great info about chipsets, but I think the spot for socket type should be made long before choosing a mobo when spec'ing a rig. Is this part of Pauls "Balanced" articles?

Crashman 02/11/2010 7:34 AM
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skora :
This is a great reference article Crash. Lots of great info about chipsets, but I think the spot for socket type should be made long before choosing a mobo when spec'ing a rig. Is this part of Pauls "Balanced" articles?



http://www.tomshardware.com/review [...] ,1289.html

nzprogamer 02/11/2010 7:53 AM
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it takes long time to read all the information here but its all good to know for 1st time builder, love it. will there be some other advice like how to keep the case cool ( how to point the fans and where )?

skora 02/11/2010 8:19 AM
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I'd say you're article came first. Nice update!!!

Crashman 02/11/2010 10:11 AM
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nzprogamer :
it takes long time to read all the information here but its all good to know for 1st time builder, love it. will there be some other advice like how to keep the case cool ( how to point the fans and where )?



Eventually there will be an update to this article:

http://www.tomshardware.com/review [...] ,1364.html

saran008 02/11/2010 10:21 AM
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Great guide for Beginners!
Tom always rocks!

ytoledano 02/11/2010 11:00 AM
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Given that the motherboard is one the least reliable components in any computer, the most important factor, IMO, is reliability.

saint19 02/11/2010 11:55 AM
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Very good article, currently I have a MSI K9A2 Platinum and works very good with my X4 955. I'm waiting for Fermi to change my mobo and RAM, and I would get an ASUS or Gigabyte...or maybe the 790FX-GD70.

EVGA build excellent mobos, the problem is that only are for Intel processors and are very expensive ($499.99), with that price you can get the half of a good rig.

anonymous 02/11/2010 12:26 PM
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I had that Gigabyte X48T-DQ6... twice. Both had some kind of error that screwed up my internet connection, so I finally switched to an ASUS P5Q Deluxe. No more problems since.

Onus 02/11/2010 12:46 PM
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I've had excellent results from ASRock, who seem to offer pretty high bang/buck. Even Foxconn is using more solid caps now, and doing so is probably what has allowed MSI to improve its quality image.

KupuAnd1 02/11/2010 12:52 PM
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I ones got a MSI board (like 5 years ago) and it was superb for reliability never dies and then I sold it. Now I got an EVGA and it is good.

Waiting for USB 3.0 to go mainstream in boards to upgrade my mobo. I think right now is the best choice for future proof.

nevertell 02/11/2010 1:09 PM
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Hey, that's my asus mobo. Although mine is underused, the other pci-e slot is empty because of the lack of money :(.

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