Trashbytes wrote on 2024-04-22, 04:09:Quick question for the Pentium 4 aficionados out there, looking at grabbing a Presshot 3.4 SL7PP to throw into the 875p board I […]
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Quick question for the Pentium 4 aficionados out there, looking at grabbing a Presshot 3.4 SL7PP to throw into the 875p board I got recently and was wondering if it would be better to stick with the 3.4 SL793 Northwood I already have?.
Reading around has them both pretty much on par till you overclock them at which point the Presscott overtakes the Northwood, also have others saying the Northwood I have is pretty much the best P4 ever made and everything after it was a mistake till Cedar Mill.
Cooling isn't an issue here but I do know the Presshots run hot along with the VRM getting a kick too.
Board if anyone is curious is https://theretroweb.com/motherboards/s/aopen-ax4c-max-ii so VRM wont be an issue.
Any thoughts ?
I suddenly remembered my Charlemagne Pentium 4 collecting knowledge
3.4Ghz 478 Northwood - will be a D1/M0 stepping = best Northwood 478 silicon (check for full rows of caps under the cpu)
3.4Ghz 478 Prescott - is just a normal Prescott with a higher multiplier although some boards might allow it to run at a lower multiplier
(3.4Ghz 478 EE - will be a M0 stepping = best Northwood 478 silicon with big cache)
Northwoods need premium silicon and a decent board to reach >3.4 Ghz (it was fun when overclocking 2.4Ghz t0 >3.2Ghz)
Run of the mill Prescotts can reach higher clocks in both 478 and 775 form
Northwoods 20 stage pipeline and smaller lower latency cache
Prescotts 31 stage pipeline and larger higher latency cache
Most retro games suitable for a Pentium 4 clock for clock will favour the Northwood.
Consider - FSB, Memory, PAT
*Edited*
Locked multiplier (up and down):
- Retail Desktop 478 Northwoods
- Retail Desktop 478 Prescotts*
- Retail Desktop 478 Extreme Editions
- Desktop 775 Gallatin Extreme Editions
- Retail Desktop 775 Prescott*
- Retail Desktop 775 Prescott XE 3.7*
*some boards allow a Low Frequency Multiplier @14x with some Prescotts
Unlocked mobile cpus (multiplier down) on desktop:
- Retail Mobile 478 Northwoods*
- Retail Mobile 478 Prescotts*
*almost all known desktop 478 motherboards will force these to Low Frequency Multiplier @ 12x
Unlocked multiplier (just down):
- Xeon 603 Foster
- Xeon 603 Prestonia
- Xeon 603 Gallatin
- Xeon 604 Nocona
- Xeon 604 Irwindale
- Pentium D Desktop 775 (Speedstep)
- Cedar Mill Desktop 775 (Speedstep)
Unlocked multiplier(full):
- A rare few Desktop ES Northwoods and Prescotts (definitely not all)
- Maybe some Retail Desktop 478 Northwoods with China as country of origin
- Retail 775 Pentium D Extreme Editions
Two ways to maximize P4 performance -
Small FSB overlock, high multipier, PAT still enabled, low latency DDR 400 2-2-2-5
High FSB overclock, low multiplier, PAT likely disabled, DDR500 3-3-2-8 or better
The former suits the high multiplier locked cpus like the 3.4Ghz Northwood
The later suits the low multiplier or unlocked cpus and will have greater memory bandwidth
One 875 selling point is PAT giving up to 10% performance increase
However it's important to realise if you overclock the FSB say over 215Mhz there are invisible straps where PAT becomes disabled depending on the bios
That AOpen is a nice premium board but not so focused for overclocking prowess as an Abit, Asus, DFI etc especially the memory voltage
So I would keep the 3.4Ghz Northwood with a small OC and tight timings, maybe one day look for an EE
If you had say an Asus/Abit 865/875 478 with lots of community vdroop and bios mods available then drop a 3.0 or lower Prescott (for lower multiplier) in for some fun and heat. Or just do it on a 775 board.