Bios slow in Ahci mode

Pointertovoid

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Hello everybody!

I have a Ga-ep45-ud3r mobo with ich10r host and Bios version F4. If Sata disk access is set in Bios to P-Ata compatibility mode, then W2k-Xp bootup is slow (35s) for still unclear reasons. And if Sata disk access is set in Bios to Ahci, then OS bootup gets very fast (OS disk is an X25-E, W2k boots in 15s and Xp in 9s, including nVidia video driver).

But then, in Ahci mode, the Bios gets very slow. The video card displays its data for a few seconds, and then the Bios takes 17s before giving control the the OS boot sequence, which is far too long.

From what's displayed, it seems that Gigabyte's Bios calls a routine supplied by Microsoft, as soon as the ich10r is set to Ahci or Raid, and this routine takes about 15s. Right?

By the way, this mobo has also a JMicron 363 P-Ata+Sata host on board, which also slowed down the Bios pretty much the same way when in Ahci mode, before I shut off the JMicron.

So:
- Can I improve this time through some settings?
- Does your mobo's Bios run faster than 17s in Ahci mode? What's your model then?
- Does an Intel mobo, with an Intel Bios, run faster than 17s in Ahci mode? Observed figures?
- Or do nVidia chipsets manage it better?

Thanks!
 

Pointertovoid

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Thanks Shadow703793! As your Mobo is quite similar to mine, it gets puzzling...

Read on a German forum that Gigabyte incorporates Intel's Ahci part in the Mobo's Bios, and older versions from Intel were slower, similarly to what I see... So:
Could you tell the version of your Mobo's Bios, and of the Ahci part of your Bios? Thanks!

And of course, more inputs are welcome!
 

Pointertovoid

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Thanks!

Meanwhile I've downloaded Bios F4 F5 F9 F11 from Gigabyte, detailed them by Cbrom v2.20 and observed the embedded Ahci subroutine provided by Intel.

F4 F5 F9 include Ahci v1.07, only the F11 (from 31st of August, 2009!) has Ahci v1.20...

Which means that I can hope a classical upgrade to F11 will bring a faster Ahci part of Bios start.
 

Pointertovoid

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Found some threads on diverse forums that observe the same effect, and their analysis and results are quite clear:
http://www.insanelymac.com/forum/lofiversion/index.php/t168690.html
http://62.109.81.232/cgi-bin/sbb/sbb.cgi?&a=show&forum=1&show=9789

It was really Intel's embedded Ahci that slows down Gigabyte's Bios, and Gigabyte took some time to include Intel's faster v1.20E Ahci.

So for my Ud3r, official Gigabyte F11 Bios should be the answer.
 
Meanwhile I've downloaded Bios F4 F5 F9 F11 from Gigabyte, detailed them by Cbrom v2.20 and observed the embedded Ahci subroutine provided by Intel.
Nice to see someone using CBRom, not many even know about it. Used it for BIOS modding a few years back, lol.

At any rate, glad Gigabyte fixed it.
 

Pointertovoid

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And it worked.

I just used Gigabyte's regular QFlash to update the mobo's Bios from F4 to F11.
This brought the embedded Ahci part by Intel from 1.07 to 1.20E, which now takes 3s instead of 17s.
So I didn't have to modify a Bios, which I was reluctant to.

Two other parts of the computer start have gotten each 3s slower: before the Bios gets the screen, and during Xp bootup. But the net sum is clearly positive, and at 4000MHz, I get a working Xp 25s after switching the power.