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Latitude C840 cpu upgrade
I have a C840 running XP which does what I need it to do. I thought I would try a cpu upgrade, I've never done a PC before. I got an Intel SL6DW-U30 cheaply and fitted it.
The BIOS still shows 1.89GHz and not the 2.5 I was expecting. I tried fiddling with the power settings from the desktop but that didn't help. There doesn't seem to be anything I can change in the BIOS unless I have missed something.
Aplogies if this is a really schoolboy error but I would like to get the new cpu working at it's proper speed.
Thanks
Intel(R) Pentium(R) 4 CPU 2.53GHz
x86 Family 15 Model 2 Stepping 7, GenuineIntel
ejn63
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April 26th, 2014 14:00
That CPU won't work on your system - not at full speed. You must use a Pentium4m -- you are trying to install a Pentium4, which will not work.
All mobile P4-m CPUs use a 400 MHz bus, which is the fastest your system will support -- the one you have requires a 533, so it's running at the right multiplier (2.5 * 100/133 = 1.89 GHz). This is as fast as it'll run on your system.
The mobile P4-m CPUs were made in volume up to 2.4 GHz , and in much smaller numbers at 2.5 and 2.6 GHz. If you want the fastest one you can get for your system, it's this CPU:
http://ark.intel.com/products/27363/Mobile-Intel-Pentium-4-Processor---M-2_60-GHz-512K-Cache-400-MHz-FSB
ps68060
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April 26th, 2014 14:00
Many thanks. I thought I had found a P4m but obviously not. It was this one:
http://www.ebay.co.uk/itm/291039384911?ru=http%3A%2F%2Fwww.ebay.co.uk%2Fsch%2Fi.html%3F_sacat%3D0%26_from%3DR40%26_nkw%3D291039384911%26_rdc%3D1
Is it safe to rely on the Intel code SL6WZ when looking for one ?
ejn63
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April 26th, 2014 15:00
The one you linked isn't a Pentium 4m -- it's a P4. There are likely more than a few S-specs that will work, but they must be Pentium M and cannot use a bus speed over 100 MHz -- if the speed is 2.53, it's a 133 MHz bus CPU and won't work
Be careful though - there are non -m CPUs at 400 MHz that won't work, either.