Intel's Long Awaited BTX Form Factor
by Purav Sanghani on November 15, 2004 5:31 AM EST- Posted in
- Cases/Cooling/PSUs
Examining ATX
The ATX form factor was designed by Intel back in 1995 to improve on the AT form factor. It brought about changes that would help standardize placements with various types of hardware, one being full length expansion cards; in original AT layouts the processor sockets were positioned at the front of the motherboard which kept full length expansion cards from being used. Now that the ATX form moved the CPU sockets to the back right corner of the motherboard full length PCI/ISA cards had plenty of room.AT also had the problem with drive bay interference since the AT motherboards were longer from front to back. With ATX the motherboard is cut wider, instead, to provide some clearance between drive bays and the board itself. Moving the CPU socket also aided in this change since there was a need for board space at the back right instead of the front left corner of the motherboard.
Some of the other changes from AT to ATX:
- Power supply connection AT motherboards used dual 6-pin connectors to power the system which was confusing and also potentially dangerous if we did not know what went where. The ATX specification implements a single 20-pin connection from the power supply to motherboard to eliminate confusion and damage to hardware.
- Power management The older AT specification also had the power button of the case hard wired directly to the power supply. The ATX specification implements the "Soft Power" feature which allows the motherboard to turn the power supply on and off by software. For example, when shutting down the Windows OS in an AT set up the system needed to be manually shut down by pressing the power button. The ATX form factor allowed the system to be automatically powered down after the OS logged off.
- Integrated I/O, peripheral connections On older AT boards, instead of having the parallel and COM ports we see at the back of the motherboards, extra cables were required to extend those features to the case. We needed to run cables from pin headers on the motherboards and mount them to the cases to be able to connect printers or other devices that used these ports. When the ATX form factor was introduced, these connectors were soldered directly on to the motherboard to both reduce the time to install components and the overall cost of a system, as well as to increase the reliability of the ports.
- Cooling and air flow Moving the CPU to the back right of the case closer to the power supply and the backside fans had a positive effect on cooling. Warm air created by the CPU would be pulled out through the back of the case as well as up through the power supply if it had a fan facing the CPU.
The ATX had a clear goal in mind; a new design that would reduce clutter, standardize component design and bring more control to the motherboard. The BTX mandate is a little less clear; reduce the PC footprint while more efficiently cooling the components. Keep this mandate in mind as it plays heavily on our conclusion.
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HardwareD00d - Monday, November 15, 2004 - link
Instead of spending all the money to research BTX, Intel should have just made watercooling standard on the Prescott CPU. Apple could have said they stole the idea from them like everything else ;)Omega215D - Monday, November 15, 2004 - link
It looks like Intel needs all the cooling it can get. I found an interesting article at Toms Hardware and here;s the closer about its heat problem "So, should a vendor release a product that is only able to run at its maximum performance under special circumstances? The fastest processors certainly are very exclusive devices, but that should not cause more troubles than necessary. The customer wants products that simply work! Think about that before releasing faster products, Intel." All I can say is wow, because I can remember my P3 866 didn't need all that cooling though now I moved on to AMD.HardwareD00d - Monday, November 15, 2004 - link
It sounds like you can essentially get the same thermal performance from an ATX case by adding 1 additional case fan.At least Intel has decided not to push this new form factor down peoples throats. Honestly, that's what I figured they'd try to do.
Gatak - Monday, November 15, 2004 - link
To have the powersupply and drive bays at the bottom is a good thing. It will keep the temperature more balanced inside the case and also provide more room at the top for cards and for exhaust fans, rather than craming everything up there.Pythias - Monday, November 15, 2004 - link
ROFL #6!!Ecmaster76 - Monday, November 15, 2004 - link
If a retail board showed up to a review with that horrible a component layout, it would be figuratively flogged.I find that the review was somewhat flawed since it failed to see what would happen with a discrete graphics card in the box. If one was used, I didn't spot it in the screenshot of the full ATX or uBTX screeshots, and it wasn't mentioned in the text.
Finally it should be mentioned that many people have theorized that the BTX layout would not work well for the Athlon64's onboard memory controller because of issues with trace layout. I'm no expert, but it does look like it might get a little tight.
ksherman - Monday, November 15, 2004 - link
"Anand's *vacation* work trip to Taipei..."Probably one of the funniest things i have read in one of your reviews.... ;)
raskren - Monday, November 15, 2004 - link
As always, so much Intel backlash, simply because, its Intel.This is how cases should have been done originally. Align all the hot components and put a fan in front and behind them. Makes sense, right?
Current ATX design is "put a fan on every hot item you have". At least that's how my case is.
LoneWolf15 - Monday, November 15, 2004 - link
To me, BTX looks like a winner for only one niche: small form factor business desktops. By that definition, I don't include Shuttle's wonderful SFF PC's which work best for home and HTPC enthusiasts. The microBTX form factor looks great for an office environment where quiet operation is a real plus, as well as power consumption, and since business PC's don't need to be cutting-edge, middle-end processors can be used that don't generate a lot of heat.Tor the enthusiast however, BTX looks like a bust to me, more of an attempt by Intel to throw the market out of whack, specifically AMD's market. Enthusiasts already have case designs meant to exhaust a lot of air and keep systems cool. Many enthusiasts LIKE a little bit larger case so that they have more expansion room, with the exception of their HTPC, and so that they can house a decent power supply for that expansion.
I see HP, Compaq, IBM, and other mainstream business computing giants adopting BTX; it will probably do well in the business market as well as in mass retail, where OEMs would rather make a system with less fans to fail and at cheaper cost. That's a pretty big sector for profit of course, but this form factor, IMO, leaves PC enthusiasts out in the cold.
Beenthere - Monday, November 15, 2004 - link
BTX is obviously NOT a great design. Intel changes sockets, Mobo and other specs periodically to FORCE people to update to their latest crap. Don't expect a rush to BTX. It's another Intel spec unlikely to ever gain foothold...For those who don't already know you can do wonders for ATX case cooling with "managed airflow". By actually directing incoming cool air to the heat sources and isolating the CPU fan from warm air in the case, no one really needs a BTX case and your PC will run much cooler with managed airflow.
While Intel definitely needs a tornado inside a box to cool their defective 90 nano CPUs, the BTX standard is just another Intel marketing scam for all practical purposes.
Just say NO !