bsel1 mod for socket 775 prescott

edited February 2007 in Hardware
I am playing with a PD-805 on a cheap PCChips P13G+ motherboard (865G chipset). The PCI frequency is not locked when FSB is raised, and the board only allows to set the FSB upto 165. After 166 FSB PCI divider should be 1/5 and I can only achieve this by changing the BSEL settings to 166FSB. Intel's PD8xx documentation indicates that LHH(BSEL[2,1,0]) settings are reserved. This should correspond to 166 FSB. Can anyone confirm this? Did anybody do this BSEL mod before with a Prescott/Smithfield to set 166 FSB? I would appreciate any info before I try this tonight.

Comments

  • edited January 2007
    Worked !!! I just put a tiny tape on the BSEL1 pad of the CPU to make BSEL[2:0] LHH and I saw that 1/5 PCI divider was activated on Clockgen after booting to Windows. But BIOS still sets FSB to 133. So the PCI frequency was 133/5. Then, I set FSB to 165, every frequency becomes normal on the motherboard but CPU is overclocked to 3.3 GHz. I am not expecting more than this on a $20 MB. PCChips is the new overclocking king :buck:

    :clap::clap::clap:

    Wait, should I try 200 FSB? NOOOOOOOOO
  • edited January 2007
    By the way, this CPU/mobo combo costed only $100 and it will be producing 800 PPD after I install 64bit Linux to run FAH SMB client.
  • edited January 2007
    hal2021 wrote:
    hey mirage, i am planning on a doing what you did with the d805 and the pcchips mobo . haven't bought yet. would you recommend either d805 or the d840 smithfield? is there a particular voltage set also. check this page out ( http://sg.vr-zone.com/?i=3931&s=1 ), also which pins or whatever is your mod on. any help is much appreciated. i've also read alittle about wiring pins together. i have my a+ but i'm nowhere near just about anybody i'm reading on. :-/
    john btw my email is [email]removed[/email]
    thanx

    Hi, PG13+ limits the FSB overclocking between 133 and 165 MHz for PD805. This is the only overclocking setting in BIOS and it does not lock PCI/AGP bus either. Default PCI divider at 133 MHz FSB is 1/4 and when PCI bus frequency exceeds ~37 MHz with higher FSB setting than 150 MHz, USB and onboard sound stop functioning with PG13+. To solve this problem, the PCI divider needs to be changed to 1/5 and I was not sure if changing the FSB frequency select signals on the CPU from BSEL[2:0] LLH to LHH. Because Intel's specification does not have any 166FSB setting, see below.
    Attachment not found.
    The Socket 775 land coordinates are given below
    Attachment not found.
    From the landout diagram given below BSEL1 land is H30
    Attachment not found.
    The coordinates are with respect to the top view of socket, but we need to make the modification on the CPU. So we need to do a mirror image conversion on the landing pads of the processor to find the correct pad. I marked the correct pad in the image of next post.
  • edited January 2007
    ... continued

    Attachment not found.
    Putting a tiny insulating tape on the pad with red circle will set BSEL[2:0] to LHH which is originally LLH.

    This worked. On the other hand I did not change the VID which can also be done with similar mods using the landing pads. PD805 draws too much power when overclocked past 3.5-3.6 GHz. I do not think PG13+ can handle that power demand. And, I know that most, if not all, PD805 can overclock to 3.3 GHZ without any voltage change. So, my target was 3.3 GHz with this motherboard and it is achieved.

    Regarding your other question: PD 840 is a 200FSB processor. I am not sure how could PG13+ can overclock past 200FSB. I do not think it is worth trying to push such a cheap motherboard beyond its specs. The procedure I described above only eliminates its limitations and does not push the operating conditions beyond its specs.
  • edited January 2007
    Interesting mod...Is there a site which shows how exactly to do this? How did you do it again? Its a little confusing :confused:

    EDIT: I went for it :)

    I covered over the BSEL shown in the picture...but it gave me only 100FSB -- leading to 2GHz CPU :o
  • edited January 2007
    ps2cho wrote:
    Interesting mod...Is there a site which shows how exactly to do this? How did you do it again? Its a little confusing :confused:

    EDIT: I went for it :)

    I covered over the BSEL shown in the picture...but it gave me only 100FSB -- leading to 2GHz CPU :o

    I just saw your PM and post. Your motherboard (ECS P4M800PRO-M) has VIA chipset, I am not sure how a VIA chipset would respond to an LHH BSEL configuration since it is actually undefined. Can you tell what CPU-Z reports as FSB and CPU speed after booting into Windows? If you do not have CPU-Z you can download from www.cpuid.com. The frequency reported by BIOS may not be accurate, if the 2GHz frequency you report is based on BIOS post screen. Did you go into BIOS and set FSB as 166 after your BSEL mod?
  • edited January 2007
    I think VIA chipsets might not work at all. Because VIA P4M800 does not have PCI lock by chipset design. The Intel 865G chipset on P13G+ has PCI lock but it was not implemented in the BIOS. So 1/5 PCI divider might not even exist in the VIA chipset since 166 FSB is not standard.
  • edited January 2007
    mirage wrote:
    I think VIA chipsets might not work at all. Because VIA P4M800 does not have PCI lock by chipset design. The Intel 865G chipset on P13G+ has PCI lock but it was not implemented in the BIOS. So 1/5 PCI divider might not even exist in the VIA chipset since 166 FSB is not standard.

    Well the motherboard supports all conroes...
    At the post screen...it said 2.66GHz...but CPU-Z showed 2GHz. It wont let me post links so I dont know how to show you my SS.
    It must have been 2GHz because the system was slower booting up.

    On ocforums dot com ...go to the CPU --> Intel section and my big thread called $85 upgrade...take a look at the last few posts, and I have the screenshot.
  • edited January 2007
    ps2cho wrote:
    Well the motherboard supports all conroes...
    At the post screen...it said 2.66GHz...but CPU-Z showed 2GHz. It wont let me post links so I dont know how to show you my SS.
    It must have been 2GHz because the system was slower booting up.

    On ocforums dot com ...go to the CPU --> Intel section and my big thread called $85 upgrade...take a look at the last few posts, and I have the screenshot.


    I checked your thread in ocforums and saw the screenshots. Are you trying to set 200FSB or 166 FSB ? The mod I did above was for 166 FSB using 1/5 PCI divider. After the BSEL mod, FSB was still 133 but 1/5 PCI divider was activated. When I set 166 FSB in the BIOS, PCI/AGP frequencies came to normal frequencies. Since 166 FSB was not used by any desktop processor, desktop chipsets and the motherboards can give unpredictable results.

    Regarding 200 FSB, I am pretty sure it can be set without any problem since 200FSB is a standard FSB frequency for Socket 775, chipsets and motherboards should know how to handle it. In addition to isolating BSEL1, you need to short BSEL2 and BSEL0 with a conductive pen to set BSEL[2:0]=LHL (see the blue line in the picture below)

    But I would not recommend this be done on your motherboard
    even with a good cooler. Because PD805 draws too much current at 4GHZ (200FSB) and I do not think the power circuit of such a cheap motherboard can sustain that power draw. Most probably MOSFETS will heat up and the motherboard will fry after some time. Again, I recommend do not try this on that motherboard.

    The performance problems you see on that motherboard can be partly due to single-channel memory of VIA chipset. Intel desktop processors give the best performance with dual-channel memory. Although the board supports Conroe, installing Conroe on that motherboard will hinder the performance of the processor just like PD805.
  • edited January 2007
    mirage wrote:
    I checked your thread in ocforums and saw the screenshots. Are you trying to set 200FSB or 166 FSB ? The mod I did above was for 166 FSB using 1/5 PCI divider. After the BSEL mod, FSB was still 133 but 1/5 PCI divider was activated. When I set 166 FSB in the BIOS, PCI/AGP frequencies came to normal frequencies. Since 166 FSB was not used by any desktop processor, desktop chipsets and the motherboards can give unpredictable results.

    Regarding 200 FSB, I am pretty sure it can be set without any problem since 200FSB is a standard FSB frequency for Socket 775, chipsets and motherboards should know how to handle it. In addition to isolating BSEL1, you need to short BSEL2 and BSEL0 with a conductive pen to set BSEL[2:0]=LHL (see the blue line in the picture below)

    But I would not recommend this be done on your motherboard
    even with a good cooler. Because PD805 draws too much current at 4GHZ (200FSB) and I do not think the power circuit of such a cheap motherboard can sustain that power draw. Most probably MOSFETS will heat up and the motherboard will fry after some time. Again, I recommend do not try this on that motherboard.

    The performance problems you see on that motherboard can be partly due to single-channel memory of VIA chipset. Intel desktop processors give the best performance with dual-channel memory. Although the board supports Conroe, installing Conroe on that motherboard will hinder the performance of the processor just like PD805.

    Well, I'm really not worried about burning this motherboard as its just a temporary transition step for me...I just cant afford to upgrade cpu/mobo/gpu and ram all at once...So I'm doing this:
    1) Basic Mobo(ECS P4M800PRO-M) and CPU(D805) -- Done for $85
    2) Quality DDR2 RAM
    3 +4 +5) DX10 GPU, C2D CPU, Good Motherboard

    This will be a much easier transition for me. I have good airflow in the case and ambient temps are like 20c

    As I'm still stuck with PC2700 RAM and a eVGA 6600GT (got zalman fan on it so give me the most performance out of it I can get)

    I'll go buy a conductive pen sometime this week and give it a shot. I just want to run it ~3.6GHz. Maybe just suicide to as high as it can go, but then run 24/7 at somewhere comfortable.
  • edited January 2007
    After 200-FSB BSEL mod, the moment you switch the computer on, it will try to boot the CPU at 4GHz. The motherboard can blow up even before BIOS post and it can also damage the processor along with it. I would not try it.

    Besides, PD805 will probably need additional voltage at 4GHz and you do not know what voltage your CPU needs at 4GHz. If it needs additional voltage, it will not post. You need to know the required voltage and set it in BIOS (or another VID mod on the CPU) before trying to boot at 4GHz. You can arbitrarily increase the voltage and try your chances but this will also increase your chances to blow up the motherboard and who knows what else along with it.
  • LeonardoLeonardo Wake up and smell the glaciers Eagle River, Alaska Icrontian
    edited January 2007
    Good work, Mirage. Overclocking on a PC Chips. That like NASCAR racing with a Dodge Neon. That deserves an award. Anyone can overclock on an Asus P5B or P5W series, but PC Chips? I like your spirit.

    Respect, Sir!
  • edited January 2007
    Leonardo wrote:
    Good work, Mirage. Overclocking on a PC Chips. That like NASCAR racing with a Dodge Neon. That deserves an award. Anyone can overclock on an Asus P5B or P5W series, but PC Chips? I like your spirit.

    Respect, Sir!

    Thanks Leo! Your recognition is most valuable. :o
  • edited January 2007
    mirage wrote:
    Thanks Leo! Your recognition is most valuable. :o

    I'm not trying to boot at the 1066FSB lol...I realize that is a BAD Move.
    I was attempting to get 800FSB (166MHz)

    I thought that was what your thread was doing...was I wrong?
    What are the pins to connect for 800FSB?
  • edited January 2007
    ps2cho wrote:
    I'm not trying to boot at the 1066FSB lol...I realize that is a BAD Move.
    I was attempting to get 800FSB (166MHz)

    I thought that was what your thread was doing...was I wrong?
    What are the pins to connect for 800FSB?

    800 FSB corresponds to quad pumped 200 MHz not 166. 166 MHz will yield 666 FSB, which is not working on your motherboard. And, the problem with 800FSB is not that your motherboard can not handle this frequency. The problem is the high current PD805 will draw at 4GHz. If you do not also raise vcore, most probably, CPU will not post at 4GHz. I am just repeating here what I posted above earlier. The pads to connect for 800 FSB (200MHz) are also given above.
  • edited January 2007
    mirage wrote:
    800 FSB corresponds to quad pumped 200 MHz not 166. 166 MHz will yield 666 FSB, which is not working on your motherboard. And, the problem with 800FSB is not that your motherboard can not handle this frequency. The problem is the high current PD805 will draw at 4GHz. If you do not also raise vcore, most probably, CPU will not post at 4GHz. I am just repeating here what I posted above earlier. The pads to connect for 800 FSB (200MHz) are also given above.

    Ok maybe I'm just very confused...So the mod at you did was to obtain what fsb?

    What I'm trying to do is (if even possible) get over the AGP/PCI lock which has limited my overclock to only 3.1GHz (I get artifacts at 162fsb)
  • edited January 2007
    ps2cho wrote:
    Ok maybe I'm just very confused...So the mod at you did was to obtain what fsb?

    What I'm trying to do is (if even possible) get over the AGP/PCI lock which has limited my overclock to only 3.1GHz (I get artifacts at 162fsb)


    The mod I did was for 166 FSB and activate 1/5 pci divider. But this does not seem to be working on your motherboard due to limited capability of VIA chipset by design.
  • edited January 2007
    mirage wrote:
    The mod I did was for 166 FSB and activate 1/5 pci divider. But this does not seem to be working on your motherboard due to limited capability of VIA chipset by design.

    So are you 100% sure it wont work, or are you just taking an educated guess?
    The PCI Divider would work for me too...are there pins just for dividers? Im guessing not.
  • edited January 2007
    ps2cho wrote:
    So are you 100% sure it wont work, or are you just taking an educated guess?
    The PCI Divider would work for me too...are there pins just for dividers? Im guessing not.

    The PCI divider is set by the chipset according to the BSEL settings of the CPU. If the chipset is not recognizing BSEL[2:0]=LHH as 166 MHz and setting the divider as 1/5, there is nothing you can do. Sorry.
  • edited January 2007
    Ok thanks for all your help!
  • edited February 2007
    ps2cho wrote:
    Ok thanks for all your help!
    you are welcome!
  • edited February 2007
    Hi Mirage,

    Great work above, did you have any trouble with Sata drives with the P13G+ and 805 setup?

    I can't get my Sata's to work once I overclock.
    Three sets of P13G+ / D805 /with Freezer 7 Pro cooler and WD 160 Sata's for school projects.

    I tried your tape method, which didn't help with the Sata problem if pushed to 165, which work at 133. Timing issue? I noticed a reference to ClockGen and found the site and downloaded the software, but stopped there.

    You mentioned 166, where PCChips P13G+ Bios only goes from 133 to 165, did you use ClockGen to get 166 or above? and set the PCI to 1/5 to get it to work?

    This might help you, I haven't overclocked since the old Abit motherboards with Celerons .... ;)

    Any suggestions?
  • edited February 2007
    Calif wrote:
    Hi Mirage,

    Great work above, did you have any trouble with Sata drives with the P13G+ and 805 setup?

    I can't get my Sata's to work once I overclock.
    Three sets of P13G+ / D805 /with Freezer 7 Pro cooler and WD 160 Sata's for school projects.

    I tried your tape method, which didn't help with the Sata problem if pushed to 165, which work at 133. Timing issue? I noticed a reference to ClockGen and found the site and downloaded the software, but stopped there.

    You mentioned 166, where PCChips P13G+ Bios only goes from 133 to 165, did you use ClockGen to get 166 or above? and set the PCI to 1/5 to get it to work?

    This might help you, I haven't overclocked since the old Abit motherboards with Celerons .... ;)

    Any suggestions?

    I do not have a SATA disk connected to this motherboard. But sound and USB were not working before I activated the 1/5 PCI divider with the BSEL mod. The problem was that the PCI clock was increasing to 41.25 (165/4) when FSB was set to 165 because of missing PCI lock. I think SATA could have created similar problems with out-of-range PCI clock. To solve this problem, I was aiming two things with the BSEL mod. First, to set FSB to 166, and second, to activate 1/5 PCI divider. I could only achieve the second with the BSEL mod. But that was no problem, I still had the option to set FSB as 165 in the BIOS. When I set FSB to 165 in the BIOS after the BSEL mod PCI clock became 33 (165/5) which made USB and sound work. I can not think of a reason why SATA would not work as well. Maybe your 1/5 divider was not activated, can you check with Clockgen and confirm that PCI frequency is ~33 at 165 FSB?
  • edited February 2007
    Thanks Mirage for the quick reply.

    I wasn't able to run ClockGen, I lost my last window's harddrive, and this computer I need....L

    Without knowing it, until I switched over to an EIDE drive after your post, I was wiping out each of my harddrives when I switched to 165. Maybe MBR? Easy to fix as I have a USB drive and Ghost to update them.

    So I will update all four drives, place tape on one P13G+ and D805 chip and no tape on another P13G+ and D805 chip and watch what happens when I try again. Probably in a few days.

    FYI: It's not the P13G+ motherboard or the D805 chip's fault as each come right back to normal as long as I attached another drive which I am now short of after my last attempt. Yes, the drives recover after being mirrored, thats why I think it's the MBR.
  • edited February 2007
    Mirage,

    Thanks, Thanks, Thanks! I wish I had tried you tape modification first!

    It works on all three motherboards. The key (for me) was to get the hard drives up and running normally and then remove them. Then do the tape modification to the D805 chip. Then up the speed to 165 in the Bios, then save. Run once without drives. Turn off machine. Then add the drives and everything works perfectly. I'm sorry I upped the speed before the tape mod, while the drives were attached, my mistake. All the drives, motherboards, and chips work great now with your tape modification!

    Again, Kudos, and thanks a lot. I may buy a few more of these overclockers, above the three I already have.
    CPU 3300.00 FSB 165 RAM 165 AGP 61.87 PCI 30.94
  • LeonardoLeonardo Wake up and smell the glaciers Eagle River, Alaska Icrontian
    edited February 2007
    I may buy a few more of these overclockers
    If you want inexpensive overclockers, and if you can still find them (eBay?), look for D915, D920, and D930. They are all 1000MHz overclock capable with good boards, stable PSUs, and good cooling - air cooling at that. They use about 30% less power than the D8XX series clock for clock and produce much less waste heat. (They are 65nm architecture versus the D8's 90nm.) Prior to my D9 collection I ran D8's. BIG difference. (Look at my signature.)
  • edited February 2007
    Calif wrote:
    Mirage,

    Thanks, Thanks, Thanks! I wish I had tried you tape modification first!

    It works on all three motherboards. The key (for me) was to get the hard drives up and running normally and then remove them. Then do the tape modification to the D805 chip. Then up the speed to 165 in the Bios, then save. Run once without drives. Turn off machine. Then add the drives and everything works perfectly. I'm sorry I upped the speed before the tape mod, while the drives were attached, my mistake. All the drives, motherboards, and chips work great now with your tape modification!

    Again, Kudos, and thanks a lot. I may buy a few more of these overclockers, above the three I already have.
    CPU 3300.00 FSB 165 RAM 165 AGP 61.87 PCI 30.94

    You are welcome :) Not bad for $100 CPU/mobo combo isn't it?
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