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BIOS edit, lost SSE instructions on AXP CPU

Joined
Jan 3, 2007
Messages
454 (0.07/day)
System Name celer
Processor Pentium 4 650 3.4GHz 2MB L2
Motherboard MSI PM8M3-V
Cooling Thermalright SI-128 SE
Memory 2048MB OCZ 2-3-2-5 2T at 200Mhz
Video Card(s) Sapphire Radeon R9100
Storage 250G Samsung 850 PRO (MZ-7KE256BW) - 1024G WD Black (WD1003FZEX)
Display(s) 19' iiyama ProLite E1980SD 1280x1024 75Hz DVI
Case Eurocase moded
Audio Device(s) onboard
Power Supply Enermax 620W Liberty
Mouse Logitech MX510 red
Keyboard eTech PS/2 keyboard
Software Win XP SP3
Benchmark Scores http://hwbot.org/submission/2455634_
Long time ago, it was my first recap - a JetWay V266B mainboard, featuring KT266A chipset and Socket A compatible. The mobo recap went well, stability was regained and it can be even well overclocked.
However I did mod the bios a little - just changing the settings to what I usually set them, so bios reset was no issue and moving the default start date to present. That was it. However just recently I noticed the AXP 2800+ CPU (run at 146 x 12.5 ATM - so it show itself as AXP 2200+) with Barton core lack SSE:

AXP2800JetWayV266BnoSSE.gif


And that is kinda weird. What could have caused it? Before it was NOT like this at all, there is the old screenshot:

axp2200104jz6.gif


...and as you can see, SSE is present.

The original bios I used to mod is there: http://ax2.old-cans.com/V266BA13.ZIP
The moded bios by latest ModBin & me is there: http://ax2.old-cans.com/V266BA14.ZIP

And the question is WHY?!

Oh, BTW, there is one more thing beside the bios mod. I was tried to force the CPU to x14 multiplier by hardwiring the CPU pins bellow the CPU socket. (using this guide: http://www.ocinside.de/html/workshop/pinmod/amd_pinmod.html ) It won't work, sadly, but could be affect the CPU instruction set features?

I used the CPU MSR to force enable SSE, and as soon as FFD show decoder stated to use it, the machine hard-crashed :(

Anyone who can tell me, what the hell went wrong?
 
LOL - the SSE instruction set was only disabled in BIOS settings, eh.
Feeling kinda embarrassed.



Anyway, I still have some questions to fullfill.

1) Can VIA KT266A chipset accept a x14 multiplier and work with it? (remember, last desktop multi is x12.5)

2) Can I update the microcode in the JetWay V266B bios to the latest version to fully support Mobile Athlons as well, as MP flag - Multiprocessing capable?

3) How can I check that the bios does not change multiplier settings to L6 settings before post?




http://www.cpuheat.wz.cz/html/AXP_multiplier_FAQ/AXP_Multiplier_FAQ.htm
"In all cases, processor will start at L3 settings (startup multiplier). However, AMD wants notebook systems to load OS at maximum frequency, therefore BIOS on mobile systems is required to do software controlled transition to highest multiplier (that is to do P-State transition) immediately after initialization. On desktop systems, there can be two scenarios. The first one is that the BIOS does not do P-State transition. In that case processor will load OS at L3 settings. The second scenario is that BIOS program is somewhat "mobile-like" and it will transition CPU to maximum multiplier - that is to L6 settings. This this second scenario you can't just cut all L6 (that would give you 24x multiplier) but instead you have to cut L6 to a multiplier your CPU can handle at startup."

http://www.cpuheat.wz.cz/html/Photos/AXP_Multiplier_Photos.htm
"Also, it is not good idea to open all L6 bridges at once because some motherboards have BIOSes that will change multiplier to L6 settings before POST."


To put things short, opening all L6 bridges on CPU give the maximum multiplier that can be set by software to 24 (eg. unlocing the CPU multiplier limits) and connecting L5 bridges give user Mobile Athlon and/or Athlon MP (Multiprocessor capable) ...

AthlonMPorMobileAthlon.gif
 
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