I'm currently looking to upgrade a CPU for an MB made for Prescott LGA775 CPUs. More specifically, I'm interested in 800FSB one as this is the limit for the P5GD1-VM MB this system has.
But to increase the reuse value for this question, an overview of the whole family of CPUs for this socket would be welcome as my research shows this proves to be an extremily confusing area of hardware.
Intel site says there are a whole multitude of CPU families with LGA775 socket:
- Prescott Celerons and Pentium 4's, including Hyper-Threading ones
- Cedar Mill Celerons and Pentium 4's
- Extreme Editions of the previous two
- Dual-core Pentium D's and Celeron D's
- Some Pentiums and Celerons with model names starting with "E"
- Core 2 Solo, Duo and Quad (plus their extreme editions)
Some hints on compatibility that I dug up but which didn't provide any hard facts and only testified about the utter chaos in this area:
- MBs for Prescotts claim to support CPUs with "Platform Compatibility Guide" ratings "04A","04B","05A" or "05B". But these appear to be mere shorthands for the maximum allowed CPU TDP (and - indirectly - the amount of power it's allowed to draw from MB, so non-standard cooling won't help here): "IIRC the 04A equates to a maximum TDP of 84W, 04B 85-115W, 05A 116-130W, and 05B 131-145W. Don't quote me on the latter two though."
- To add insult to injury, Intel doesn't specify these ratings in CPU specs at its site, appearing to have abandoned them shortly after introduction.
- Cedar Mill CPUs appear to be powered by lower voltage than Prescotts but it's unclear how compatible this is from MB standpoint (MBs are known to have been able to adjust CPU voltage for quite some time)
- MBs designed for single core CPUs are rumored to not support dual-core CPUs. But Hyper-Threading is dual-core from external standpoint - it still handles two execution pipelines at once (thus requires bus locks and related circuitry), just not as effectively.
- The tested CPU list for my MB shows Prescotts and, surprisingly, Celeron D's - which are supposed to be two steps apart in the evolution chain!
- Pentium 4's and Pentium D's are said to be very much alike and an MB may be able to run a Pentium D even if its tested list doesn't include it.
