Useful stuff about the Presario 1600 series

This page is primarily aimed at the 1670 to 1694 models, but some information here may be useful for other models too, specifically those with AMD processors such as some of the 1200 series units.

After a bit of research, I have found many of the DIP switch settings for these laptops, to enable the user to upgrade the processors to a higher specification.

On the Compaq website, there is a service and maintenance guide, in which there are details on how to dismantle the laptop in order to replace all of the components.

I discovered that the AMD processors in the models outlined above are fitted into ZIF sockets, so they are removable, and what is more, it is relatively easy to do so.

Once you have got a hard copy of the Service and maintenance guide pages that you need, and removed all the obstacles from your laptop, (having first ensured that you are properly earthed!), you can endeavour to replace/upgrade the processor.

I have found that these Laptops can be clocked to numerous speeds, up to 600 MHz in fact, and at several voltage settings. Below I list the DIP switch settings to enable the various speeds and voltages.

One thing to note is that the original CPUs in most of the Presario series are not necessarily the mobile variants, just the desktop versions, so any of the K6-2 or K6-3 series will install, just make sure that you set the right voltage before installation.

One little tip: before you change any of the switches, write down the default settings, just in case you lose your way or get distracted, then you can at least revert back to the original configuration.

There are two DIP switch blocks near the processor. Both are very tiny, so I use a straightened paper clip to push the switches, through the amber coloured protective film.

On the large block (SW1), switches 1, 2, and 3 control the multiplier settings.

so to get:

2.0x 1=on 2=on 3=off

2.5x not available

3.0x 1=off 2=on 3=off

3.5x 1=off 2=off 3=off

4.0x 1=on 2=off 3=on

4.5x 1=on 2=on 3=on

5.0x 1=off 2=on 3=on

5.5x 1=off 2=off 3=on

6.0x 1=on 2=off 3=off

Switches 4 and 5 control BUS speed.

So to get:

75MHz 4=on 5=on

83MHz 4=off 5=on

95MHz 4=on 5=off

100MHz 4=off 5=off

To recap, for example, to get 500 Mhz:

1=off 2=on 3=on 4=off 5=off

NEVER CHANGE SWITCHES 6 to 10. This is very important!

(New !) DIP switches 6, 7, and 8, define the type of display that you have fitted (TFT, HPA, size, make etc), and it is critical that you never change them! If you really need to know the settings, I can provide them on request.

DIP switches 9 and 10 are still under investigation, I have an idea of what they may do, so watch this space in the coming weeks for some more settings.

On the smaller block (SW2), switches 1 to 4 control voltage.

So to get:

1.8v 1=off 2=off 3=on 4=off (New !)

2.0v 1=off 2=on 3=off 4=off

2.1v 1=on 2=off 3=off 4=off

2.25v 1=off 2=off 3=off 4=off

2.3v 1=off 2=off 3=off 4=on (New !)

There are probably more settings than these, but these are all I know about at the moment. If anyone gets to know any settings that I have missed, please let me know!

K6+ (Plus) series of CPUs are ideal as an upgrade for the laptop user, because the heat generated by these chips is greatly reduced.

Beware that the K6+ series use a core voltage of 2.0v, so take care! They have a design operating range of 1.9v to 2.1v, so there is some versatility.

See my page on AMD K6 CPUs for details on the ones to get as an upgrade, and a few facts and figures about them, even a bit on overclocking!

Please note the new charges that apply for me to answer questions, at the base of the main page.

This is my e-mail address: mgrudkin@yahoo.com