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KT4V BIOS Doesn't Support 153 FSB?

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Oct 19, 2002
Anchorage, Alaska
i'm using the KT4V mobo and when i try to set the FSB to 153 with any vcore setting and any memory settings it wont boot up, but if i set it to 144 FSB and then use Fuzzy Logic in Windows to up the FSB it'll work. anyone know why?
first, some more specs on your systemwould help

second, as far as i can see, the 1/5 divder hasnt kicked in... maybe 166 FSB would be better

(166/5=33) (153/4=35.75)

oh, and dont use fuzzy logic, do tit manualy, in the bios
ummm some specs huh.....

AthlonXP 1600+
Samsung PC-2700 RAM
Maxtor 60GB HD
TDK 32x10x40 CD-RW
VisionTek GeForce 3

dunno what else you want

and any FSB above 151 wont let my comp boot up if i do it through the bios, my comp gets unstable at around 157-158(through fuzzy) and it auto-bluescreens at 159-166. i haven't tried any higher through fuzzy

oh yea, kinda off topic, but i've discovered that raising the fsb causes my cd drives to not be able to instal programs off of burned cds. any insight on that?
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ahem, try NOT using fuzzy logic... enter your BIOS by hitting the "delete" key upon start-up, and change every thing manualy.

your pci is running too high, and i think fuzzy is the culprit...

you should be able to run 166 FSB w/stock voltage

i dont like fuzzy logic anyway...
Ya. 160 FSB / 4 = 40 PCI speed, while 166 / 5 = 33. OFTEN, on many boards, FSB = 166 is MUCH more stable than FSB of 150 to 165.

1) So FIRST, try setting 166 FSB in the bios.

2) IF that by itself doesn't work, try lowering the CPU multiplier, to say 8. (You didn't mention if your CPU was unlocked, I'm assuming YES?)

3) If your CPU is NOT unlocked, (A) unlock it :) or (B) start to increase your CPU voltage. I have had a couple 1600+ that would not run at 166 at stock voltage.

I currently have TWO MSI KT4VL boards, both at 166 with XP1600 and samsung PC2700 ram. One XP needs voltage, the other doesn't.

You really shouldn't have problems at FSB = 166.

Good luck.
thanks for the replys guys. i havent unlocked the cpu yet so i cant lower the multiplier. but i have tried raising the voltage but without success, at most it will give me one or two more FSB. and again, my BIOS will NOT let me go higher than 151 FSB before it wont boot up at all.
I think you might be missing the point about the divisor's. Have a mooch 'round, do some reading, then you might understand a little more.

Try some of the sticky's for starter's.
i've tried to go to 166FSB a couple more time and i've noticed that the computer itself sounds likes it booting up but its just not showing anything on the monitor. maybe the computer is fine but either the video card or the monitor just start to choke at that high of an FSB, could this be a possibility?
Firstly it's nice to see you've added a 'sig' (perhaps you could make it a little smaller? Check this out, Smaller, (size 1 is good, it takes up less space on the site).;)

Secondly I found this paragraph very helpful,
By changing the mult or the fsb you get a higher cpu speed. However it is not as simple as just raising both the mult and fsb. First off you need to realize that by raising the FSB you are also affecting every component in your system. The most dangerous thing about overclocking is affecting the harddrive. You want to be careful about the hardrive going above 39mhz because it can get currupted if you do. The default speed of your hardrive, and every other PCI card is 33mhz. Now most of you are probably asking how in the world do i tell how fast the harddrive is running? Well most people who are reading this have either a motherboard based on the via KT266a or KT333 chipset. Both on stock valuses use a 1/4 pci divisor to determine how fast the PCI slots are running. On a stock value of 133mhz, you jus need to divide it by 4 and you will see that it turns out to 33mhz.
(Dear moderator, I hope I'm not overstepping any boundary's quoting a 'sticky', but I think it's for a good cause;))

Thirdly, I'm not 'having a go', but I have found that you get better responses to questions if people think you've had a look around to find the answers but, maybe you've just been unlucky and followed the wrong links and got a little lost, and they try to put you back on the right track.

The answers are out there. I'm learning too, as you can see from when I registered, but as far as I'm aware, anything on the IDE ports (eg. CD ROM, hard drive etc.) is controlled by the PCI. Thus if your system 'throws it's hand in' @153mhz fsb, it maybe that your PCI is'nt happy @ 38.25mhz(153/4 (1/4 divisor), but might be happy @ 33.2mhz(166/5 divisor).

Happy hunting.
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see, the thing is i understand what you mean and i really am trying. but what i have said a lot so far is that something goes wrong at 166 FSB. i'm thinking now that for some reason either the video card isn't handling it (it's AGP and i dunno what the safe limits are for that), the monitor can't handle it, or the computer just won't boot up at 166 FSB. :p

oh yea, thanks for the size suggestion, but what size should i put it at?
Did you get a 'D' bracket with your mobo? If so have you fitted it, and what does it show when your trying to boot at the higher setting's? Pages 1-8 + 1-9 of your 'quick user's guide' tell you what the lights mean.;)

P.S. I can't get my system to run @ 105mhz!! nevermind 133 or even 153mhz:(
P.P.S. Try size 1

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well i hooked up the d-bracket and i tried the FSB at 158, 162, and 166 to be sure and sure enough they all hung when testing the video card. so i guess my video card just isn't up to snuff when it comes to OC'ing :p
yo guys!

anyone have ever had experience overclocking a xp 1800 on either a kt3 ultra board or a kt4 ultra. i can't go higher than 146 fsb (yes it's locked) and no..... i don't use fuzzylogic (it sucks)

i don't think it's the memory holding me down, i have kingston pc 2700