finding max FSB - Techist - Tech Forum

Go Back   Techist - Tech Forum > Computer Hardware > Overclocking and Modding
Click Here to Login
Closed Thread
 
Thread Tools Display Modes
 
Old 01-28-2006, 04:56 AM   #1 (permalink)
Super Techie
 
NickFas's Avatar
 
Join Date: Nov 2005
Posts: 273
Default finding max FSB

how do i find the maximum fsb for my particular motherboard. I saw thi s on overclock.net and i was curious what he meant by the following sentence.

Quote:
4) Raise your memory timings, and/or change your CPU/memory ratio so that your memory’s FSB is always at/below it’s rated speed. This should insure that your memory won’t be limiting your FSB, just your mobo.
Hopefully someone can make more sense of this than i did.
Nick
__________________

__________________
Proud owner of the only hampster powered rig on these boards.
NickFas is offline  
Old 01-28-2006, 08:31 AM   #2 (permalink)
Ultra Techie
 
Disillusion's Avatar
 
Join Date: Nov 2005
Posts: 810
Default

You would change the CPU to RAM ratio only if you have RAM that doesn't overclock well. Lets say for instance that your CPU can take 300 MHz, but the RAM can only take something like 250 MHz. When you raise the FSB (HTT with an AMD) it will automatically raise it for the RAM as well, so you must set up a ratio if the RAM is maxing out and your CPU isn't. For instance, if you set up a 5:1 ratio, if you increase the FSB from 250 MHz to 255 MHz, the RAM is only going to get 1 MHz more instead of 5 more.

The only way to find out the max FSB your motherboard can support is if your CPU can be overclocked (and is stable) further than the motherboard can go. Other than that, there is no way to find out the max FSB the motherboard can do.
__________________

__________________
CPU: Intel i7 2600k @ 4.4 GHz
Cooler: Cooler Master V8
Mobo: ASRock Z68 Extreme3 Gen3
RAM: Corsair Vengeance 16 GB DDR3 1600 MHz
GPU: EVGA 560 Ti
HDD: Cruicial M4 SSD 128 GB
HDD 2: WD VelociRaptor 300 GB
PSU: Corsair TX650w
Case: Corsair 600T Graphite Series
Disillusion is offline  
Old 01-28-2006, 12:20 PM   #3 (permalink)
Monster Techie
 
idiotec's Avatar
 
Join Date: Jan 2005
Posts: 1,748
Default

RAM is linked to the FSB, so raising the FSB also increases the speed of the RAM. All that is saying is to increase the RAM divider so you have headroom on raising the FSB before the RAM starts running at speeds higher than it is designed to.

The other thing you would want to do to test your max FSB is lower the CPU multi as low as it can go and make sure to lower the LDT multi as well.

One example, lets say you chip runs at 2Ghz and your running DDR400, default settings are:
CPU multi x10
FSB 200
RAM 200
LDT x5

Now lets say you do the following:
Lower CPU multi to x6
RAM divider to 2:1 (may look like 100Mhz in BIOS)
Lower LDT to x3

Now you can raise the FSB to 333 without the CPU, RAM or LDT being overclocked, get it? The results would be:

CPU = 6x333 = ~2Ghz
RAM = 333/2 = 166
LDT = 3x333 = ~1000Mhz

The main point is when trying to find one components max speed, you want to take other components out of the equation.
__________________

BE HEARD - Techonvent
DS3 | E6400 - 3.2GHz 24/7 | 2GB OCZ PLat. PC6400 | 6800GT | Zippy 460W
What the world needs is more geniuses with humility, there are so few of us left.
idiotec is offline  
Old 01-28-2006, 01:15 PM   #4 (permalink)
Ultra Techie
 
Disillusion's Avatar
 
Join Date: Nov 2005
Posts: 810
Default

Ah, yes, idiotec. I forgot about dropping the multiplier down. I guess that would be a good way to find max FSB.
__________________
CPU: Intel i7 2600k @ 4.4 GHz
Cooler: Cooler Master V8
Mobo: ASRock Z68 Extreme3 Gen3
RAM: Corsair Vengeance 16 GB DDR3 1600 MHz
GPU: EVGA 560 Ti
HDD: Cruicial M4 SSD 128 GB
HDD 2: WD VelociRaptor 300 GB
PSU: Corsair TX650w
Case: Corsair 600T Graphite Series
Disillusion is offline  
Old 01-28-2006, 03:10 PM   #5 (permalink)
Super Techie
 
NickFas's Avatar
 
Join Date: Nov 2005
Posts: 273
Default

What is the LDT?
__________________
Proud owner of the only hampster powered rig on these boards.
NickFas is offline  
Old 01-28-2006, 10:15 PM   #6 (permalink)
Ultra Techie
 
Join Date: Dec 2005
Location: NY, USA
Posts: 771
Default

LDT = hypertransport...you want to try to keep this around 1000mhz...fsb (or HTT) x LDT = hypertransport Mhz
__________________

__________________
  • AMD FX 8350 Black Edition
  • XFX R9 390 8GB
  • 16GB (8x2) GSKILL DDR3 1866mhz
  • GIGABYTE GA-990FXA-UD3 AM3+
  • Aspire X-Plorer Silent Case
  • PC Power & Cooling Silencer 610W Continuous
  • 180GB Intel 520 SSD
  • Vizio 32" TV (1920/1080)/Acer P221W 22" Widescreen LCD (1680/1050)
Twizted_3kgt is offline  
Closed Thread

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are Off




Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -5. The time now is 08:22 PM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.