Unlocking AMD XP / Overclocking and FSB

Discussion in 'General Hardware' started by TheBlueRaja, Aug 21, 2002.

  1. TheBlueRaja

    TheBlueRaja BR to Some

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    Hey Folks,
    I think im finally going to unlock my AMD XP2000 so i can reduce the clock speed and up the FSB. But i wanted to get a few things straight first before i do it as im still a little unclear on a couple of things. My ultimate goal is to set the chip to think its an AMD 1600 and then up the FSB as far as it can go. So...

    1) Why do i need to unlock the chip in order to make it look like a AMD XP 1600 for example, cant i just change the multipliers from AUTO on the motherboard down to say, 8x, and then up the FSB, using this to overclock the motherboard? And if not then what exactly does unlocking it do?

    2) To unlock the chip all i need to do is connect the L1 Bridge right?

    3) What would limit the top end of the FSB setting now that the Processor is set to a lower clock speed (assuming of course the the FSB doesnt push the unlocked chip past what it can handle) as far as i am aware the FSB is the link between the processor and the North Bridge..

    4) Any tips or useful points to watch out for?

    Thanks
     
  2. Howling Wolf

    Howling Wolf We did not deserve this !

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    I don't quite follow you...

    If you unlock your cpu to lower its multiplier... and then overclock the fsb... total you will get a cpu running at a probably lower frequency, Mhz speaking... which will result in a decrease of the cpu horsepower...
    Am I wrong ?

    If you manage to unlock your 2000+, why not up the multiplier by +0.5 or +1 ? And overclock the fsb as far as you can, provided you have sufficient cooling ?

    Tell us !
     
  3. TheBlueRaja

    TheBlueRaja BR to Some

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    What i want to do is up the FSB as far as possible. To do this i need to reduce the speed of the processor.

    Why? Well if i can convince the system that it is in fact an AMD 1600 instead of a 2000 then the processor will run at a lower speed as you say, probably at around 1200 mhz or what ever a 1600 runs at.

    However, i will then use the FSB to increace the speed of the processor AND with it the rest of the system instead of using the mulitpliers, thereby removing the bottleneck that is the max speed my processor can run at when it is "locked".

    Therefore, i will effectively have an AMD XP 2000+ with the mobo thinking its an AMD XP 1600, which i wil then overclock to AMD XP 2000 speeds using the FSB setting in my BIOS, this will give me a MUCH higher FSB.

    Its just a way of tricking the system into thinking it has a 1600 in it, (when in fact it has a 2000) which you then overclock using the FSB. Which in the process speeds up everything else in the system. E.g AMD XP2000 running with 190 Mhz FSB.

    I hope this helps...
     
  4. gonaads

    gonaads Beware the G-Man Political User Folding Team

  5. Howling Wolf

    Howling Wolf We did not deserve this !

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    Ok BlueRaja, I get the point now ! But will your ram support a fsb this high ? What ram do you have ? Brand or noname ? PC2700 running higher than rated ?
    BTW, how do I set the ram to run at 166x2 independently instead of 133x2 (Cpu fsb) ? I'm not in front of my puter now, in the bios I have 3 options for the ram: auto / 1:1 / 4:5 , something like this... Thanx !
     
  6. UofEEE

    UofEEE Guest

    If you really want a 1600+, newegg.com has them for like 54 bucks....
     
  7. blinden

    blinden OSNN Senior Addict

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    this is a rediculously bad idea, just up the FSB and keep the MULTIPIER (not the clock speed) the same (clock speed = Multiplier x FSB) you'll get much better performance then doign whatever you are trying to do here
     
  8. UofEEE

    UofEEE Guest

    If your 7VRXP is anything like mine, the northbridge is pretty stinkin hot. Put an active cooler on it w/ dose of some Arctic Silver. I've pushed my FSB to about 142 and it won't budge past there. I've got Crucial memory, so it's quality. However, I believe the limiter is the fact that it's not cooled well.
     
  9. TheBlueRaja

    TheBlueRaja BR to Some

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    Hmmm....

    Well, i still think that this is a good idea, and other people have tried this successfully, however after reading the comments posted here regarding RAM im not sure that it would be able to handle it. I have TWINMos DDR 2700 ram, which runs no problem when i clock the ar*e off it but whether this will hold up to an increace in the FSB without any sort of cooling is another matter.

    Im getting 11500 3dMarks now anyhoo with my Ti4400 so i think i may just leave this for the time being until i get some heat sinks for my GFX card memory and memory chips.

    blinden, you should have a look at the forums over at amdmb.com if you think im talking out my butt here, it has been done and by a lot of people by the sound of it. There are even some people on the 3D Mark score comparison website that have managed to get their FSB up to 198Mhz (although i doubt by this method alone)
     
  10. Sazar

    Sazar F@H - Is it in you? Staff Member Political User Folding Team

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    um mate... you don't WANT to get to 190mhz on your fsb... if you do AND run stable without your box in a cooler... you let me know coz I know I Can't do that..


    see stats below... I am running my stock 1900+ with 144 fsb and it is stable as hell.. I can clock her up higher but then I don't want it to become unstable... and I don't really need that speed...

    thats the equivalent of what? a 2100+ and YEs I am happy coz I spent 90 odd dollars on the OEM cpu..

    you need to unlock in order to oc your pc.. thing you really are unlocking is NOT higher bus speed... but the clock multipliers... I want to unlock my pc and will do so later and I am going to be able to get maybe 0.5-1.0 extra on my multipier..

    whats that mean?

    basically my STOCK runs at 12 x 133 = 1600mhz...
    now it is running faster 12 x 144 = 1728mhz

    as you can see right there that is not a bad oc for 11mhz gain... BUT as you clock higher your AGp and PCi bus speeds change and I don;t want to go too high and risk killing my usb/pci/agp devices right now...

    I am happy with my stable oc..

    with a 13x multiplier available.. at my STOCK fsb... of 133... my clock speed will be a great 13x133=1729MHZ with STOCK fsb...

    all I will need to make it same speed rating as a 2200+ will be to clock fsb higher... if I can do it to 144 like now my speed will be a total of 13x144=1872 which is more like 2300+ per what xp will tell me...

    of course I am more than likely to sell my current rig to my friend and use the money to buy a stock 2400+ and say to hell with it
    coz right out the box I can oc my 2400+ to close to 2.3 ghz aircooled (with good HSF..)

    :) worth it?

    you betcha... eh...

    :D
     
  11. Sazar

    Sazar F@H - Is it in you? Staff Member Political User Folding Team

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    btw...
    my stock pc with load = 38C
    my pc @ 2000+ load =40C
    my pc @ 2100+ load =42C

    so the increase in temp is not bad... only 4c...

    a good board and a good cooler will let you oc better.. make sure you have quality memory too else it will keel over and beg to be buggered with a little fluctuation in fsb... :)