At last I decided to check what Mr Natural changed in his bios. Here is the result, based on comparing his TH7-II Raid 7F bios with the official Abit 7C bios. I can imagine results would be very similar for other m/b.
CPU Microcode
No change at all, the 7c already supports CPU Id 0x0F12, 0x0F13, 0x0F21, 0x0F23, 0x0F24. In other words the current 533MHz Pentium 4 are supported.
The new C1 stepping, however will require addition of the 0x0F27. It's easily done, AnnaMaria has done it already, and I suspect Abit will do it soon since they have added it recently to the BD7-II and they have started work on a TH7-II beta bios.
HPT Raid Controller BIOS
Mr Natural updated it to a more recent one. Abit has now done the same in the latest beta. Since then there is a more recent one, which Abit has started using as well.
Enable BIOS hidden settings
PCI configuration
Spread Spectrum Modulated
Display Fan Off In Suspend
Hide settings
CPU L3 Cache
Change default values
CPU L3 Cache:
from Enabled to Disabled
System BIOS cacheable:
from Enabled to Disabled
Video bios cacheable:
from Enabled to Disabled
AGP Fast-Write:
from Disabled to Enabled in Fail-Safe settings
unchanged as Enabled in Optimized settings
Incremented bios revision number
That's all folks!
Apart from that I could not find anything else modified. Sorry to say I am a bit dubious about Mr Natural claims of how his intimate knowledge of assembly is required to produce his bioses... All that is needed to perform the above is:
CBROM to change bios components
MODBIN to enable/disable settings and change default values
CTMC to examine/modify CPU microcode (not used by Mr N)
I also do not understand why he would not want to disclose the changes he made.
Below are a few explanations/comments about some of the settings which have been mentioned:
AGP Fast Writes
Allows the AGP device to write to the bus without calling an interrupt. In fact, it's forced behaviour, unlike the 2x or 4x modes which are always agreed upon by the chipset and the video card. So if you enable this for the extremely slight performance boost, you'll get instability within any 3D accelerated application when using a video card that doesn't support Fast Writes.
Comment: most recent graphic cards support this setting, if in doubt, check. Enable it if supported.
Spread Spectrum Modulated
This compromises system stability by performing frequency modulation on the system clock. Timing critical devices, such as NICs and SCSI may have problems. It's there to reduce EMI problems by making sure the system isn't using any one frequency for too long.
Disable it.
On a 1GHz system, 0.25% will result in a 2.5MHz fluctuation in CPU core frequency. Not nice. Always, always, always disable this when overclocking. If you have the Smart setting, the system will shut off the clock to unused slots, so use this if you have it.
Comment: I am not sure why Mr Natural claimed that it increased stability when overclocking with RDRAM. Maybe he knows something I don't.
From my experience I have not noticed any stability difference. What I noticed though is turning it off will increase the frequency by the equivalent of half a step. This might take you over your stability threshold if you are borderline.
As anyone experimented more or can enlighten us?
L3 Cache
This type of cache is becoming more prevalent as microprocessor manufacturers ship more processors with L1 and L2 cache built into the processor. L3 cache is then the extra cache that sits on the motherboard between the processor and main memory, since the processor already contains L1 and L2 cache.
Comment: This can only increase performance. However Mr Natural turned it off.
After looking at Intel spec, it would seem that Intel had plan to add a L3 cache to the Pentium 4 but had some problems and removed it. The Itanium will feature it.
I could not find anything about the TH7-II having a L3 cache onboard.
If it's not there I am not sure turning it off would increase stability or performance.
CPU Microcode
No change at all, the 7c already supports CPU Id 0x0F12, 0x0F13, 0x0F21, 0x0F23, 0x0F24. In other words the current 533MHz Pentium 4 are supported.
The new C1 stepping, however will require addition of the 0x0F27. It's easily done, AnnaMaria has done it already, and I suspect Abit will do it soon since they have added it recently to the BD7-II and they have started work on a TH7-II beta bios.
HPT Raid Controller BIOS
Mr Natural updated it to a more recent one. Abit has now done the same in the latest beta. Since then there is a more recent one, which Abit has started using as well.
Enable BIOS hidden settings
PCI configuration
Spread Spectrum Modulated
Display Fan Off In Suspend
Hide settings
CPU L3 Cache
Change default values
CPU L3 Cache:
from Enabled to Disabled
System BIOS cacheable:
from Enabled to Disabled
Video bios cacheable:
from Enabled to Disabled
AGP Fast-Write:
from Disabled to Enabled in Fail-Safe settings
unchanged as Enabled in Optimized settings
Incremented bios revision number
That's all folks!
Apart from that I could not find anything else modified. Sorry to say I am a bit dubious about Mr Natural claims of how his intimate knowledge of assembly is required to produce his bioses... All that is needed to perform the above is:
CBROM to change bios components
MODBIN to enable/disable settings and change default values
CTMC to examine/modify CPU microcode (not used by Mr N)
I also do not understand why he would not want to disclose the changes he made.
Below are a few explanations/comments about some of the settings which have been mentioned:
AGP Fast Writes
Allows the AGP device to write to the bus without calling an interrupt. In fact, it's forced behaviour, unlike the 2x or 4x modes which are always agreed upon by the chipset and the video card. So if you enable this for the extremely slight performance boost, you'll get instability within any 3D accelerated application when using a video card that doesn't support Fast Writes.
Comment: most recent graphic cards support this setting, if in doubt, check. Enable it if supported.
Spread Spectrum Modulated
This compromises system stability by performing frequency modulation on the system clock. Timing critical devices, such as NICs and SCSI may have problems. It's there to reduce EMI problems by making sure the system isn't using any one frequency for too long.
Disable it.
On a 1GHz system, 0.25% will result in a 2.5MHz fluctuation in CPU core frequency. Not nice. Always, always, always disable this when overclocking. If you have the Smart setting, the system will shut off the clock to unused slots, so use this if you have it.
Comment: I am not sure why Mr Natural claimed that it increased stability when overclocking with RDRAM. Maybe he knows something I don't.
From my experience I have not noticed any stability difference. What I noticed though is turning it off will increase the frequency by the equivalent of half a step. This might take you over your stability threshold if you are borderline.
As anyone experimented more or can enlighten us?
L3 Cache
This type of cache is becoming more prevalent as microprocessor manufacturers ship more processors with L1 and L2 cache built into the processor. L3 cache is then the extra cache that sits on the motherboard between the processor and main memory, since the processor already contains L1 and L2 cache.
Comment: This can only increase performance. However Mr Natural turned it off.
After looking at Intel spec, it would seem that Intel had plan to add a L3 cache to the Pentium 4 but had some problems and removed it. The Itanium will feature it.
I could not find anything about the TH7-II having a L3 cache onboard.
If it's not there I am not sure turning it off would increase stability or performance.