Question about ATX sizes and case

Andy Pandy · 23 Nov 2006 at 18:11

Hi, i have a coolermaster case. Its about 3-4 years old. Quite big and very heavy. I have a atx 2.0 psu in there right now. If i wanted a ATX 2.1 or + would it work in my case or would i need a new one.

shadowscotland · 23 Nov 2006 at 19:55

it should fit

Andy Pandy · 23 Nov 2006 at 20:17

so you dont need a atx 2.1 designed case to run atx 2.1? phew.

i thought if you wanted a different version of atx your case would have to change each time

Tetras · 23 Nov 2006 at 21:04

Dimensions are identical from 2.0 to 2.1 (and 1.3 etc for that matter) and the changes inside are very, very minor.

The only thing worth considering (physically speaking) are cases where the PSU is placed at the bottom and it has short cables or fan(s) in a bad place with little ventilation.

There are also some cases where the PSU doesn't have much breathing space and a few (PSUs that is) are particularly large (especially high wattage models and one or two modular ones).

shadowscotland · 23 Nov 2006 at 21:11

The revisions relate to the spec of the psu and its cables.
History of atx psu below from here

http://www.formfactors.org/developer/specs/ATX12V_PSDG_2_2_public_br2.pdf

1.0 Feb, 2000 • Public release

1.1 Aug, 2000 • Increase 3.3 V current; add more explanation for power sharing; do minor edits and format fixes

1.2 Jan, 2002 • Typical Power Distribution. Change +5V loading on all power supplies distribution tables defined in DG to 0.3A
• PS_ON# Add text “The power supply should not latch into a shutdown state when PS_ON# is driven active by pulses between 10ms to 100ms during the decay of the power rails.”
• Remove –5V from all power distribution tables.

1.3 April, 2003 • Update Power and Current guidance
• Added efficiency guidance at typical and light load
• Increased min efficiency at full load from 68% to 70%
• Serial ATA* connector definition added
• Acoustic levels added for low noise power supply design
• Reformat and update revision table
• Update Disclaimers
• Remove guidelines for ATX
• Remove guidance for –5V rail
• Updated guidance for Energy Star and stand by efficiency

2.0 February, 2003 • Added Terminology section
• Updated power and current guidance
• Includes 250W, 300W, 350W, and 400W guidance
• Updated cross regulation graphs
• Updated load tables
• Updated required efficiency targets. Added recommended efficiency targets.
• Increased required minimum efficiency at typical and light load.
• Main Power Connector changes to 2x12.
• Aux power connector removed.
• Required Serial ATA Connector.
• Isolated current limit on 2x2 connector for 12V2 rail.

2.01 June, 2004 • Updated 3.3 V remote sense pin # on the main power connector
• Updated 12V2 DC Output Noise/Ripple information
• Removed -5V reference
• Updated 5Vsb maximum current step
• Modified 115 VAC Frequency for the Voltage Hold-up Time

2.1 March 2005 • Add 450W guidance
• Current requirements updated: 250,300,350,400W
• Load table Updated
• Cross loading NEED TO UPDATE: from 250W to 450W.
• Efficiency requirements increased
• 3.3.3 5V standby current increased

2.2 March 2005 • Corrected 12V2 load levels in Tables 3-7
• Added label to Figure 5
• 4.5.1 Added High Current Series wire terminals for ATX Main Power Connector
• 4.5.2 Added High Current Series wire terminals for +12 V Power Connector