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What are your thoughts on overclocking an AMD Athlond 900 Mhz MMX computer made by Compaq? I have a GeForce 4 Ti just bought and put in and I'd like to increase the AMD speed to the fullest without buying a new computer. I've never overclocked anything before so I need some help.

--G4ce_user

Hi, if you specify what motherboard you have in your computer I could tell you if you can OC by increasing the FSB, as the older Socket/Slot A motherboards only go up to 100mhz (200mhz DDR) FSB, and therefore you cannot OC the CPU. Although you can OC the CPU by linking the L1 cache on the CPU itself by using the old pencil trick, or even better, using solder. I must warn you though that this voids the warrenty on the CPU and means total disaster if the worse was to happen. You should be able to get that Athlon 900 to arond 1100mhz at least. It is probably better bet to OC using the FSB clock on the board (if the board will suport it), as unlocking the multiplyer will, as I say, void the warranty, but the disadvantage to this is that highering the FSB also increases the running speed of the rest of the computer (the AGP/PCI bus) which can cause instabilities before you reach the limit of the CPU itself. If you can, tell me what make/type of memory you have too, because OCing on the FSB also depends a lots on how far the memory can go aswell, as that probably limits the CPU before the CPU limits itself. Tell me things like the memories clock speed (PC100/133mhz...DDR?) and it's rated CAS Latency.

Also let us know what type of Athlon 900 MHz that you have, is it a SlotA (big slot processor sticking up out of the motherboard with the HSF to the side) or SocketA (smaller socket processor with the HSF on top)? If it's a SlotA, is it based on the Thunderbird core (256K on-die Cache) or the Classic Althon (512K off-die cache)? If it's a SocketA, is it a Duron or Thunderbird?

This will let us know if it's possible to unlock your processors mutiplier the easy way (as pattouk2001 mentioned). If you have a SlotA CPU, then your overclocking options are going to be pretty limited.

And as mentioned before, knowing what motherboard you have will be very helpful (if you don't know just give us the model # of the Compaq and we can look it up).

I got most of this information from two of those diagnostic/system info programs (Sandra and Compaq’s Diag).

AMD Athlon M4 (Thunderbird) – I think SocketA. I don’t know who manufactured the motherboard, but I’m thinking Compaq themselves did. It uses a VIA Tech chipset VT8363/5 KT133/KM 133 controller.
External clock: 100MHz
Max Processor speed: 1250 Mhz

I have Micron 128MB DIMM SDRAM. I was planning on installing more later. I was unsure what you meant on CAS latency so I just put the whole line:

Memory Module 1 : Micron 8LSDT1664AG-10EB1 5C007A43 128MB 8x(16Mx8) SDRAM PC100-222-622 (CL3 upto 125MHz) (CL2 upto 100MHz)

Compaq Presario 5000 series – 5WV280

If you need more info I can try to get it

Oh also:

Front Side Bus Speed: 2x 100Mhz (200Mhz data rate)
Max FSB speed / Max Memory Speed: 2x 133Mhz/ 1x 133Mhz

Hi, yeh, your going to have to unlock your muiltiplyer using the old pencil trick as your motherboard only supports 100mhz (200mhz DDR) Athlon type "B" CPU's. Looking at the memory you have, you should be able to get the CPU to about 1.1ghz. Happy OCing!

what is the "old pencil trick"?

Hi. When you take the HSF off the CPU, there should be 8 little (there very small) metallic dots in pairs of 2 which are labelled "L1". You simply connect the 4 pairs together using a pencil, as the grafite is conductive, which will unlock the muiltiplyer in the BIOS, provided your board supports this feature.

This is the only way to overclock it right?

Thanks for everything

Hi. Yeh, unfortunately it is mate.

Here is a guide that might help:

http://www.motherboards.org/articlesd/h ... /41_1.html

It comes complete with pictures (and unfortuneatly pop up ads). There are other guides out there as well but it was the first one that came up for me on Google.