Question Mobile Pentium 4 HT; can it be sub'd for a Pentium 4 HT?

dorkshoei

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Mar 15, 2017
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I picked up an old G4V620-B1 motherboard in order to support an ISA card I have.

It came with a 2Ghz Celeron installed. I'd prefer to install a P4 HT.

According to the manual the following CPUs are supported:

* Intel® Pentium® 4 Processor with Hyper-Threading Technology 533MHz system data bus (see note)
• Intel® Pentium® 4 processor (478-pin) 400/533MHz system data bus
• Intel® Celeron® processor (478-pin) 400MHz system data bus

note:
• CPU - an Intel® Pentium® 4 Processor with HT Technology
• Chipset - an Intel® chipset that supports HT Technology
• BIOS - a BIOS that supports HT Technology and has it enabled
• OS - an operating system that includes optimizations for HT Technology

https://en.wikipedia.org/wiki/List_of_Intel_Pentium_4_processors#Pentium_4_HT
SL6K7 (C1) SL6JJ (C1) SL6S5 (C1) SL6SM (C1) SL6PG (D1) SL6QC (D1) are all 3.06ghz, 533mhz fsb, socket 478

https://en.wikipedia.org/wiki/List_of_Intel_Pentium_4_processors#Mobile_Pentium_4_HT

SL77P, SL7DT and SL7NA are all 3.06ghz 23x socket 478 533mhz fsb

I'm not sure if these will work? What about other multipliers?
 
In a word, no. It may well work but you would be stuck at the lowest multiplier of 12 in any desktop board for 1.6GHz maximum speed. If this is acceptable to you (for power savings... but then you usually wouldn't select a P4) then you could try it but it wouldn't be much faster than the Celeron.

There is only one Northwood P4 HT that board is designed to accept and that is the desktop 3.06. All of the other ones use a 800FSB or are Prescott which are not supported by that board.

There are also LGA 775 and 1155 boards with ISA slot if you want more performance
 

dorkshoei

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Mar 15, 2017
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In a word, no. It may well work but you would be stuck at the lowest multiplier of 12 in any desktop board for 1.6GHz maximum speed. If this is acceptable to you (for power savings... but then you usually wouldn't select a P4) then you could try it but it wouldn't be much faster than the Celeron.

There is only one Northwood P4 HT that board is designed to accept and that is the desktop 3.06. All of the other ones use a 800FSB or are Prescott which are not supported by that board.

There are also LGA 775 and 1155 boards with ISA slot if you want more performance

Thanks.

So just SL6K7 (C1) SL6JJ (C1) SL6S5 (C1) SL6SM (C1) SL6PG (D1) SL6QC (D1)
https://ark.intel.com/content/www/u...chnology-3-06-ghz-512k-cache-533-mhz-fsb.html

Is there a resource which explains the 12x as I'm not understanding. In the Wikipedia table mobile SL77P seems to have the same multiplier and fsb. How do you determine that Prescott isn't supported, based on something in the mobo datasheet?

As for ISA I thought Socket 478 had the last chipsets which offered DMA support for ISA?

I wish 4GB ram was an option on the motherboard but 2gb is the max. It came with 1gb which i'd like to cheaply upgrade to 2gb.

Thanks again for the reply.
 
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The desktops of the time had a nominal maximum clock and the OS would reduce the multiplier to save power when performance was not required, sort of a de-turbo or un-boost. When in the BIOS or DOS it would run at maximum clock all of the time.

Laptops on the other hand booted and ran mobile chips at the lowest multiplier all of the time, then used extra pins in the socket to request more performance when it was needed. Given that these pins weren't attached to anything in the sockets of desktop boards, no higher multiplier could be requested. ASUS made an adapter (the CT-479) to not only wire up these pins but also convert S478 to lower voltage S479 to allow the use of Pentium-M in desktop boards.

The Mobile Pentium 4s had a lowest multiplier of 12x and the Pentium-M 6x (essentially like a Pentium-III adapted to the P4 FSB).

Pretty much all ISA expansion cards put their own ISA Busmaster DMA controller on the card itself to avoid the 4.77MHz performance issue, with the notable exceptions of floppy, parallel and serial port cards.

As for the memory, well at least your board takes DDR, as the 845 chipset also included a SDR memory controller. SDRAM of course only comes in half the density and thus capacity of DDR1 per stick.
 

dorkshoei

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Mar 15, 2017
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Pretty much all ISA expansion cards put their own ISA Busmaster DMA controller on the card itself to avoid the 4.77MHz performance issue, with the notable exceptions of floppy, parallel and serial port cards.

As for the memory, well at least your board takes DDR, as the 845 chipset also included a SDR memory controller. SDRAM of course only comes in half the density and thus capacity of DDR1 per stick.

Thanks!

I'm using the motherboard to hold some old ISA development cards (dual i860 being one). Very little documentation on the card, so I figured I'd go for a safe bet which I believe the Socket 478 boards is. Three ISA slots is nice.

Maybe there is a better option but I'd have to find it and they don't show up often on ePay.

I just ordered 2 matching sticks of RAM. I guess 2GB will be the max. Current Linux was struggling badly with 1GB but I'd not optimized it's installation at all.