Prescott may not mean what you think.
What is Prescott?
Prescott is the Intel® codename for their latest generation of Pentium® 4 desktop CPUs based on 90nm technology. They run hotter than previous Pentium 4 chips.
Background: Initial ‘Prescott’ CPU’s were introduced in February of 2004 as Socket 478 parts. These initial ‘Prescotts’ are pin compatible with the already existing P4 CPU’s (codenamed Northwood). However Intel later introduced the LGA 775 part, which needs a new motherboard. The issue is further clouded since both ‘Prescott’ versions and the Northwood core are all called Pentium 4.
What does ‘Prescott Ready’ mean?
Not much, frankly—especially considering how confused the market has become. Intel has recently discussed or released a host of new standards and technologies and many people, even including industry insiders, seem to be mixing some or all of these other distinct topics up into a confusing and foggy “Prescott Ready†catch-all category. The following subjects are often confused with “Prescottâ€:
ATX12V v2.0
BTX
PCI Express
i915/i925X chipsets
Background: many aspects of the new technology are designed to work with or enable other aspects—for example, ATX12V v2.0 power supplies are better able to power motherboards with the PCI Express bus—but that does not make them ‘the same thing.’ Each of the subjects listed above deserves its own treatment and should be understood both for itself and in relation to the other subjects.
What about these ‘Thermally-Advantaged Chassis,’ or TAC cases?
Excellent question! If “Prescott Ready†means anything, it means that. Since “Prescott†P4s run hotter than past CPUs, Intel has introduced a standard for ‘Thermally Advantaged’ chassis. These TAC cases meet minimum requirements for providing cool air to the CPU cooler, so they can be presumed likely to work with a Prescott core P4.
Since “Prescott Ready†is already being used confusingly in connection with things that are not ‘Prescott,’ that label has become meaningless right from the start. And since Intel already has a category (TAC) for cases that are likely to work with Prescott-based systems, we think TAC is more meaningful and it is unnecessary to introduce a new label.
Can a non-TAC case work with a Prescott chip?
Maybe yes. And a TAC case could conceivably fail to keep a Prescott CPU cool. ‘TAC’ is an observation, not a guarantee.
Background: ALL THINGS BEING EQUAL, a TAC case has the best chance to perform well with a Prescott core CPU. But if you block the vents, or put it near a sunny window, all bets are off. Similarly, depending on the total system you build (i.e. how hot the other components are), a case that missed the TAC case by one or two degrees might work fine and never encounter a problem. Think of TAC as a recommendation, not an absolute.
What about Prescott and Power Supplies?
There’s no such thing as a Prescott Ready power supply. Anyone who claims that is either trying to sell you a bill of goods, or doesn’t know what they’re talking about. Either way, you might want to avoid them.
Okay, what about ATX12V v2.0 and Prescott?
ATX12V v2.0 is a new standard for power supplies and motherboards, and among other things has been implemented to provide more power to the new PCI Express bus. An ATX12V v2.0 power supply can be distinguished by a 24 pin main power connector (instead of 20 pins) and dual +12V rails (harder to see, but the box or manual should list that).
Since most future motherboards will meet this standard, and since most of the new P4 CPUs Intel sells will be ‘Prescott,’ there will in fact be a seeming link between these technologies—but not a requirement. Most new boards on the market now will work fine with a PSU that meets either new or old spec. When you decide to add a PCI Express card to your system, you will be better off with a PSU that meets the new spec.
Background: ‘Prescott’ doesn’t really create problems for power supplies; it’s motherboards where the confusion will arise. When a consumer buys a ‘Prescott’ CPU or a new motherboard, did they get the Socket 478 version or the LGA 775 version? It makes a difference!
24 pins, eh? Is EPS12V compatible then?
Some users are quite familiar with this standard for server motherboards and power supplies. The EPS12V spec. also sports a 24 pin main power connector, but often the +12V connector is 8 pins, not 4 pins. So you’ll want to be careful to get a PSU that matches your motherboard’s connectors. Antec’s server PSU includes both 8 and 4 pin secondary connectors for wide compatibility, but unless you are quite familiar with these standards you may find it better to go with ATX12V v2.0 across the board.
You mentioned chipsets.
Yes, but only because so many others out there are getting confused on this. Chipsets are a motherboard (and I/O bus) issue, not a power supply or chassis issue. If your power supply works with your motherboard, and both fit in your chassis, we’ve done our job.
And BTX?
That’s a coming standard for chassis. Many things about BTX will be new and different—but that’s a topic for another day. By the time you find yourself worrying about BTX, Prescott will be old, old news.