BIOS Questions

I've read the tutorials on here and have some questions before I do anything to my computer. First, I'll start off with my system specs:

Gigabyte GA-EP45-UD3P
EVGA Nvidia GeForce GTX 280
Corsair 750TX
Intel Core 2 Duo E8500 3.16GHz
G.SKILL PI Black 4GB (2x2GB) DDR2 800 4-4-4-12 Timing
Western Digital Caviar Black 640GB
Windows Vista Ultimate 64-Bit
Arctic Cooking MX-2 Thermal Compound
Xigmatek HDT-S1283 120mm Rifle w/Retention Bracket

The mobo has a robust graphics booster with the settings; Auto, Fast, and Turbo essentially overclocking the card without having to do it from windows. There is also the C.I.A 2 (Computer Intelligent Accelerator 2) which overclocks the PC and the same goes for memory. The RAM is automatically set on Turbo and my FSB:DRAM is 5:6. Should I keep the RAM on Turbo? I was wondering what you guys thought about these stock overclocking systems (even though I don't plan to use them).

Other BIOS Questions
CPU Clock Ratio - 9.5x stock for the E8500. Is there a benefit to lowering this number and raising the FSB.

Fine CPU Clock Ratio - Raises the CPU Clock Ratio by .5 Is this something you guys recommend doing?

CPU Host Frequency - The mobo manual says it should be set in accordance with the CPU specifications. So for the E8500 it should be set a 333GHz so 9.5x333=3.12GHz. Wouldn't overclocking throw off the balance they say you should keep (or are they telling us this to protect the CPU?)

PCI Express Frequency - Put on 100MHz MANUAL

CPU Clock Drive - Adjusts the amplitude of the CPU and North Bridge Clock; 800mV Default. Should I keep this the same?

PCI Express Clock Drive - Adjusts the amplitude of the PCI Express and North Bridge Clock; 900mV Default. Should I keep this the same?

CPU Clock Shaw - Allows you to set the CPU clock prior to the North Bridge Clock; Default - 0ps Should I keep this the same?

MCIT Clock Shaw - Allows you to set the North Bridge Clock prior to the CPU Clock; Default - 0ps Should I keep this the same?

Extreme Memory Profile (X.M.P.) - Allows the BIOS to read the SPD data on XMP memory modules to enhance memory performance. Should this be enabled? (Default is disabled)

MCH Frequency Latch - Allows you to fix the chipset frequency at system boot up. Should I keep this on auto?

System Memory Multiplier (SPD) - Should I keep this on auto?

Should I adjust any of the memory timing besides (trd phrases, DIMM clock scews, channel A/B timing) the initial 4-4-4-12 Timings? (which I did when I first built the computer)

DDR Write Training - Keep on auto?

Channel A/B Driving Settings - Should I leave this alone?

Load Line-Calibration - Enabling adjusts the Vdroop keeping the CPU voltage more constant under light and heavy loads. Should I keep this disabled?

CPU VCore - Will change after initial OC


The following are all set on auto, are there any of these I should change?
CPU Termination
CPU PLL
CPU Reference
MCIT Core
MCH Reference
MCH/DRAM Reference
ICH I/O
ICH Core
DRAM Termination
Channel A Reference
Channel B Reference

DRAM Voltage - Should be set to the recommended voltage listed in the memory documentation?

Hard Drive Detection - Any benefits from taking this off of auto?

Should I enable C2/C2E State Support and C4/C4E State Support for power savings?


I know this is a lot of questions but I would appreciate it if someone could help answer them. Like I said before I already read the other tutorial.

-Thanks
16 answers Last reply
More about bios questions
  1. Any help?
  2. pmacdonald said:
    I've read the tutorials on here and have some questions before I do anything to my computer. First, I'll start off with my system specs:

    Gigabyte GA-EP45-UD3P
    EVGA Nvidia GeForce GTX 280
    Corsair 750TX
    Intel Core 2 Duo E8500 3.16GHz
    G.SKILL PI Black 4GB (2x2GB) DDR2 800 4-4-4-12 Timing
    Western Digital Caviar Black 640GB
    Windows Vista Ultimate 64-Bit
    Arctic Cooking MX-2 Thermal Compound
    Xigmatek HDT-S1283 120mm Rifle w/Retention Bracket

    The mobo has a robust graphics booster with the settings; Auto, Fast, and Turbo essentially overclocking the card without having to do it from windows. There is also the C.I.A 2 (Computer Intelligent Accelerator 2) which overclocks the PC and the same goes for memory. The RAM is automatically set on Turbo and my FSB:DRAM is 5:6. Should I keep the RAM on Turbo? I was wondering what you guys thought about these stock overclocking systems (even though I don't plan to use them).

    Other BIOS Questions
    CPU Clock Ratio - 9.5x stock for the E8500. Is there a benefit to lowering this number and raising the FSB.

    Fine CPU Clock Ratio - Raises the CPU Clock Ratio by .5 Is this something you guys recommend doing? If you want to max out your overclock then it may help

    CPU Host Frequency - The mobo manual says it should be set in accordance with the CPU specifications. So for the E8500 it should be set a 333GHz so 9.5x333=3.12GHz. Wouldn't overclocking throw off the balance they say you should keep (or are they telling us this to protect the CPU?) - this is the FSB freq. No problem in increasing it

    PCI Express Frequency - Put on 100MHz MANUAL. Keep as 100MHz

    CPU Clock Drive - Adjusts the amplitude of the CPU and North Bridge Clock; 800mV Default. Should I keep this the same? Yes.

    PCI Express Clock Drive - Adjusts the amplitude of the PCI Express and North Bridge Clock; 900mV Default. Should I keep this the same? Yes.

    CPU Clock Shaw - Allows you to set the CPU clock prior to the North Bridge Clock; Default - 0ps Should I keep this the same? Probably.

    MCIT Clock Shaw - Allows you to set the North Bridge Clock prior to the CPU Clock; Default - 0ps Should I keep this the same? Probably.

    Extreme Memory Profile (X.M.P.) - Allows the BIOS to read the SPD data on XMP memory modules to enhance memory performance. Should this be enabled? (Default is disabled). Don;t know.

    MCH Frequency Latch - Allows you to fix the chipset frequency at system boot up. Should I keep this on auto? Yes.

    System Memory Multiplier (SPD) - Should I keep this on auto? No. Adjust to get correct RAM timings

    Should I adjust any of the memory timing besides (trd phrases, DIMM clock scews, channel A/B timing) the initial 4-4-4-12 Timings? (which I did when I first built the computer). Not usually worth it for a first OC attempt. Increase to 5-5-5-15 or 6-6-6-18 until your system is stable.

    DDR Write Training - Keep on auto? Don;t know

    Channel A/B Driving Settings - Should I leave this alone? Don;t know

    Load Line-Calibration - Enabling adjusts the Vdroop keeping the CPU voltage more constant under light and heavy loads. Should I keep this disabled? No. Enable it. You'll fnd it far easier to get a stable overclock without the CPU voltage wondering aroudn all over the place!

    CPU VCore - Will change after initial OC


    The following are all set on auto, are there any of these I should change?
    CPU Termination
    CPU PLL
    CPU Reference
    MCIT Core
    MCH Reference
    MCH/DRAM Reference
    ICH I/O
    ICH Core
    DRAM Termination
    Channel A Reference - only change if you are having RAM stability issues
    Channel B Reference - only change if you are having RAM stability issues


    DRAM Voltage - Should be set to the recommended voltage listed in the memory documentation? Correct

    Hard Drive Detection - Any benefits from taking this off of auto? None, unless your system isn;t recognising your hard drive(s)

    Should I enable C2/C2E State Support and C4/C4E State Support for power savings? Disable until your OC is stable


    I know this is a lot of questions but I would appreciate it if someone could help answer them. Like I said before I already read the other tutorial.

    -Thanks



    hth. couldn't answer all your questions i'm afraid.

    btw, probably = i don't know for sure but your suggested answer is 'probably' correct!
  3. CPU Clock Ratio - 9.5x stock for the E8500. Is there a benefit to lowering this number and raising the FSB.
    Theorectically, yes. Practically, I have never seen much difference.

    Fine CPU Clock Ratio - Raises the CPU Clock Ratio by .5 Is this something you guys recommend doing?
    Yes. Otherwise you do not gain the full use of the internal multiplier of the CPU.

    CPU Host Frequency - The mobo manual says it should be set in accordance with the CPU specifications. So for the E8500 it should be set a 333GHz so 9.5x333=3.12GHz. Wouldn't overclocking throw off the balance they say you should keep (or are they telling us this to protect the CPU?)
    Default is DISABLED. You need to enable this to be able to OC.

    PCI Express Frequency - Put on 100MHz MANUAL
    One of the few settings I leave on AUTO.

    CPU Clock Drive - Adjusts the amplitude of the CPU and North Bridge Clock; 800mV Default. Should I keep this the same?
    PCI Express Clock Drive - Adjusts the amplitude of the PCI Express and North Bridge Clock; 900mV Default. Should I keep this the same?
    CPU Clock Shaw - Allows you to set the CPU clock prior to the North Bridge Clock; Default - 0ps Should I keep this the same?
    MCIT Clock Shaw - Allows you to set the North Bridge Clock prior to the CPU Clock; Default - 0ps Should I keep this the same?
    These 4 settings I don't have on my GA-EP35-DS3P. But I would say that if you do not know why you want to change them, don't.

    I leave memory settings on AUTO except SYSTEM MEMORY MULT. which I set to "2". You can fine tune memory performance last after OC'ing everything else. Multiplier on "2" means FSB and RAM run 1:1.

    Channel A/B Driving Settings - Should I leave this alone? Don't havethis setting. But I would say that ...

    Load Line-Calibration - Enabling adjusts the Vdroop keeping the CPU voltage more constant under light and heavy loads. Should I keep this disabled?
    Mine is set on AUTO

    CPU VCore - Will change after initial OC


    The following are all set on auto, are there any of these I should change?
    CPU Termination
    CPU PLL
    CPU Reference
    MCIT Core
    MCH Reference
    MCH/DRAM Reference
    ICH I/O
    ICH Core
    DRAM Termination
    Channel A Reference
    Channel B Reference
    I don't have all of these. You may need to boost MCH and FSB voltages a little.

    DRAM Voltage - Should be set to the recommended voltage listed in the memory documentation? Yes. Or even increase a little for stability.

    Hard Drive Detection - Any benefits from taking this off of auto? I don't think so, but I could be wrong.

    Should I enable C2/C2E State Support and C4/C4E State Support for power savings? I don't.

    -------------------
    GA-EP35-DS3P
    Q9550 OC'd to 3.6 GHz/TRUE
    4 GB Crucial Ballistix
    GTX260-216
    2.5 TB WD HD's
    650 w Antec TP3
    Antec 900
    ----------
    Overclocking since 1978 - Z80 (TRS-80) from 1.77 MHz to 2.01 MHz
  4. Thanks for the replies. I am about ready to start overclocking my computer. The first thing I will do is increase my CPU Host Frequency. What increments should I increase this by? Mine is currently set at 333.

    My second question is should I increase anything else with this on the first go around? And if so by what increments?
  5. It's worth working out what your max FSB speed is first, before you start to increase CPU speed.

    So, try decreasing your CPU multiplier to keep CPU speed down, then increase CPU Host frequency to 350. Increase at 10 increments and run prime 95 for an hour. If you get a fail then increase your NB voltage and FSB termination voltage as required. Your mobo supports 1600FSB, so you can go up to 400. Anything you can get over that is a bonus!

    Once you've worked out the max FSB your motherboard can handle then start to increase your CPU multiplier and CPU voltage.
  6. Thanks for the reply Fruity. I have just went into bios thinking I was ready to OC and came back with a few questions.

    1)
    In BIOS it says my default CPU Clock Ratio is 8 (+.5 for the Fine CPU Clock Ratio) and is running at 333 with the CPU Host Frequency. That's 2.83GHz, but in CPU-Z and on in my welcome menu it says I'm running the E8500 at 3.16GHz... So what's it running at?

    2)
    My CPU VCore is set on auto and is at 1.25 Should I manually set this to 1.25 so it doesn't increase and overheat when I increase the CPU Host Frequency? or leave it on auto?

    3 & 4)
    Are the system temps in your BIOS accurate?

    Under my system temps I have the following options:
    CPU Warning Temp - Disabled
    CPU Fan Fail Warning - Disabled
    etc...

    Should I enable these? It seems like these would be my fail safe if something were to get too hot.


    Based on what Fruity said should I start my OC at the 8.5x Multiplier and 350MHz CPU Host Frequency?
  7. Hi pmacdonald,

    1, Best guess is that Speedstep (aka EIST) is reducing your multiplier to 8x as an energy saving measure. Disable this option is BIOS and see if it changes things. Alternatively, monitor CPU-Z (or equivelant) while running Prime95 and see if your processor speed increases. If neither of these increases your 'in windows' processor speed then post back....

    2, Once you've solved point 1, reduce your multiplier to keep CPU speed down. Keep your voltage set manually to 1.25V. Gradually increase the FSB til you max out (i.e. the max FSB that your mobo can support). You will need to slowly increase your northbridge and FSB VTT to acheive this. Some alteration of the Northbridge Strap may also be necessary to maintain 1 : 1 RAM ratio.

    3, No, the temps in BIOS are not accurate. Choose a programme to use and stick with it. Personally I use Everest, a lot of other advocate Realtemp. Err on the side of caution and don't allow anything to come within 10°C of max temp under sustained load if you're unsure.

    Set CPU warning temp to 70°C or there abouts.. Enable CPU fan fail warning.


    It's not a five minute job to get a big overclock - allow 3 days minimum!!
  8. Thanks again for the quick reply.

    I've set everything as suggested and am running a torture test on Prime95 but which test should I be running?

    Under the CPU voltages all of them were set to auto. The only one I put to manual was the Vcore. Should the others be set to manual as well and kept at their stock level?

    I put the CPU Multiplier at 8.5 and the CPU Host Frequency at 350 to start off with. I also turned the Load-Line Calibration on and set the PCI Express Frequency to Manual at 100MHz.

    Thanks again for the help so far. (Problem #1 is fixed. CPU-Z is reading a higher processor speed).
  9. All looking good then.
    Drop your multiplier down to 6x and keep CPU core the same (it prevents any chance of overclocking the CPU at this point).
    I'd run a blend test for an hour at each level until you think you're close to your FSB limit. Once you're at 400MHz and you know the minimum NB & FSB VTT voltages required for stablity, then continue to increase but run for 4 hours. Continue to increase until you are at the FSB threshold run for 12 hours minimum....
    It takes more work to get the FSB stable than anything else - the CPU is easy!!

    Once you have a pass then you can increase the CPU multiplier and CPU voltage to get the final overclock.
  10. Sounds good, thanks! I still would like to know if I should leave all of the other CPU Voltages on auto though?

    Besides that I've passed the first test with no errors ran for an hour (didn't expect any just wanted to get a feel for the overclocking process).

    I'll now change the multiplier to 6x and raise the FSB up by another increment of 10.

    How do you know when to increase the NB & FSB VTT Voltages? When I get my first error? And then how much should I raise them up by? (and do I do this one at a time?)

    My DRAM Voltage is set on auto as well as the main timings. Should I change these to manual?
  11. Indeed, raise NB & FSB VTT when you get a crash during Prime95 or boot failure.

    Raise one at a time or not? It's up to you. My method involves raisng both til the ceiling is found, then dropping back whichever is most over it's design limit until a fail occurs.
    The other can then be reduced untl failure. If both are within design limit then you don't have much to worry about (providing NB temp is ok).

    How much to raise by: "a notch or two" in BIOS. The higher you go, the voltages required for stability raise exponentially. Or at least seem to. I don't know your BOS well and can't remember what the increments are.

    Set DRAM to the spec of your RAM. Don't leave on auto. Increase main RAM timings by at least 1 point each (e.g. 4-4-4-12 goes to 5-5-5-15 or 6-6-6-18). Once your OC is stable you can look at reducing the timings back down again.

    Don't leave you other CPU voltages on Auto if you can avoid it, although at this stage it won't matter too much since the CPU isn't being overclocked. Not sure what they are supposed to be set to for your CPU, i'll have a look around and see what I can find....
  12. No need to look up the standard voltages. In BIOS it tells me the standard/default setting next to the options I can change. I've put the settings on manual at the standard level for the CPU Voltages and the RAM Voltages. I raised the memory timings to 5-5-5-15 and put the Voltage for the RAM at 1.8V. I ran this test for about an hour and it passed (6x @ 360MHz).
  13. *New Questions*

    CPU-Z says my DRAM Frequency is at 444MHz and this increases as the CPU Host Frequency Increases. I believe this is due to the MCH Frequency Latch setting and Memory Frequency Multiplier setting. These are both on auto at the moment. What should I change them to?

    FSB:DRAM is running at 5:6 right now. How do I get this 1:1?
  14. *New Questions*

    CPU-Z says my DRAM Frequency is at 444MHz and this increases as the CPU Host Frequency Increases. I believe this is due to the MCH Frequency Latch setting and Memory Frequency Multiplier setting. These are both on auto at the moment. What should I change them to?

    FSB:DRAM is running at 5:6 right now. How do I get this 1:1?

    Edit: *UPDATE*

    My 4th trial:
    DRAM Frequency crept up to 444.0MHz

    E8500 - 6x @ 370MHZ
    50Min=1 Error (On one core)
    FATAL ERROR: Rounding was 0.5, expect less than 0.4
    Highest Temp: 41*C
    Lowest Temp: 21*C

    After this run I put the following back on auto:
    DRAM Termination
    Channel A/B Reference
    CPU Termination
    CPU PLL
    CPU Reference
    and changed the DRAM Voltage to 1.820V

    My 5th trial found an error in 2 minutes.

    I loaded my optimized defaults and ran another test which is looking good. What could have caused those problems above? Should some of my settings be kept on auto (I turned the settings on all the voltages to Manual and put them at standard/default)?

    After reading a little more this is what I've done. I've kept every setting on auto except the VCore, DRAM, ICHCore, MCHCore, and CPU Termination Voltages. I've also set the PCI Frequency to 100MHz on manual. I then set my DRAM to 1:1 at 400MHz but I was only able to achieve this by setting my CPU Host Frequency to 400MHz @ 9x (+.5) with the test I'm running so far there have been no errors. I assumed I'd have to raise one of the voltages but so far so good.
  15. hi, sorry for the late response. been a tad busy for the last couple of days.

    It's worth checking your RAM voltages. I think the memory you have is 2.0v - 2.1v. That would certainly cause an error....

    http://newgskill.web-bi.net/bbs/view.php?id=g_ddr2&page=1&sn1=&divpage=1&sn=off&ss=on&sc=on&select_arrange=headnum&desc=asc&no=132
  16. That may have been the wrong link for your RAM.

    If you're not sure check what it should be here:

    http://newgskill.web-bi.net/bbs/zboard.php?&id=g_ddr2
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