
Originally Posted by
rge
With turbo off, I can run 20x200, 191x21, 182x22 all prime stable at same vcore of 1.35 bios, loadline on. But I think I finally got lucky and got a nice chip, makes up for my E8600 and E8400.
With turbo on, 182x22 gives me 4/4.2 which is still prime stable, turbo is 182x23 or 4.186 and prime stable.
However with 20x200, turbo on gives me 23x200 or 4.6ghz for turbo, and I have to increase my vcore to ~1.5ghz just to boot. Same goes for 19x191, turbo gives me 23x191. With i920 20x200 turbo will give you 21 multi, so this issue will not occur on i920 at 20 multi.
In fact if I decrease the multi to 15 and bootup, turbo still gives me 23 multi for +8 turbo, then drops to 15 multi on load. Have been doing beta testing for unclewebb and reading about turbo....but difficult when bios itself is ? doing things correctly.
So I run 182x22, in order to run turbo enabled. The million dollar ? is, when intel says +1 turbo do they mean +1 over stock, in other words bios is acting correctly and will always go to turbo of stock multi +1 (23 on i940) regardless of multi setting in bios, or is it a bios bug and the chip is supposed to run at +1 over bios multi. If turbo is +1 over stock, then those with i920 only will be able to run 20x200 turbo enabled, and those with i940 will only be able to run 22x182 turbo enabled. My guess is on i920 19x211 will not be stable with turbo on, as your turbo will then be 21x211 or 4.4.
Given msr editor shows max turbos listed as 23,23,23,24 on chip, and that is probably what sets turbo multi, I am starting to think it is not a bios bug, and that turbo enabled will bring your multi all the way up to stock +1.
Which means I need a 9 multi to bring my mem up to stock, b/c I can not run turbo 20x200 (which would allow x8 multi for 1600 native mem speed), so I am stuck at 182x22....or buy some 1800 and run x10 multi. That will be one advantage of i920, for those that can run 20x200 stable.
According to intels white paper on turbo, which I posted in realtemp thread, it states max turbo is +1 (again ? over stock or +1 over bios) when 1 to 4 cores are loaded providing there is enough power headroom and within other operating parameters. For example light load of even all 4 cores still yields turbo. To get the +2 or 24 turbo, I had to shut off 3 cores in bios and only truly run 1 (intel states this in white paper), which begs the question what is the purpose of 24 multi, how many are going to shut off 3 cores in bios to get it.
Earlier in i7 thread I posted a prime run off 20x200, that was with turbo off.
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