Results 1 to 6 of 6

Thread: my minds gone blank, fsb

  1. #1
    Member
    Join Date
    Oct 2003
    Location
    Liverpool
    Posts
    70
    Thanks
    0
    Thanked
    0 times in 0 posts

    my minds gone blank, fsb

    some please explain how upping the fsb/multiplier will make the agp, pci etc run faster

  2. #2
    Member
    Join Date
    Oct 2003
    Location
    Liverpool
    Posts
    70
    Thanks
    0
    Thanked
    0 times in 0 posts
    i remember now, is it fsb
    shared by shared by 4 - AGP
    shared by 2 - PCI


    ??

  3. #3
    '~'+'~' Enverex's Avatar
    Join Date
    Oct 2003
    Location
    West Midlands
    Posts
    901
    Thanks
    0
    Thanked
    0 times in 0 posts
    • Enverex's system
      • Motherboard:
      • Gigabyte H77n-WiFi
      • CPU:
      • Intel i5-3570K with Scythe Shuriken
      • Memory:
      • 16GB Crucial Ballistix Tactical 1600Mhz
      • Storage:
      • Samsung 840 500GB SSD
      • Graphics card(s):
      • MSI GTX 670 2GB OC Power Edition
      • PSU:
      • EVGA SuperNOVA 550W G2
      • Case:
      • Silverstone Sugo SG11
      • Operating System:
      • Windows 10 Pro 64bit
      • Monitor(s):
      • LG 42LW550T 42" TV
      • Internet:
      • BT Infinity
    Depends on the multiplyer that the motherboard is using. Some have it locked so nothing changes when you increase the FSB, and others use deviders, so that when it reaches 166 (from 133) it hits the next devider and the PCI bus goes back to normal.

    So at 133mhz FSB the PCI bus is the FSB / 4 (33mhz) and the AGP bus is the PCI * 2 (66mhz).

    NS

  4. #4
    Banned
    Join Date
    Jul 2003
    Location
    House without a red door in Birmingham
    Posts
    1,595
    Thanks
    0
    Thanked
    0 times in 0 posts
    Modern P4 and nF2 Skt mobos impliment a PCI/AGP lock. Older mobos use a divider of the FSB in order to derive the speeds. It's largely the divider which dictates what FSB a given mobo can use. For instance KT400 were designed for 333FSB (2x166mhz) so used a 1/5 divider (PCI=33mhz while 1xAGP is double that). KT600 are designed for 400FSB (2x200mhz) so use a 1/6 divider. They support lower dividers for the lower FSB too of course, it is usually an automatic thing rather than user selectable. The problem with dividers is when you try to run at unusual FSB speed, such as 380FSB (2x190mhz) on KT400 where PCI is 190/5=38mhz and hence 1xAGP=76mhz (4xAGP=304mhz and AGP8x=608mhz). It's considered within PCI spec to range from 30mhz to 36mhz although some devices are more sensitive/picky than others. You may also find things like IDE are derived form the PCI speed and as such you can experience HD corruption past a certain speed. All things to bear in mind when o/c'ing divider based mobos esp when you are dealing with a locked CPU (or where your mobo's max multiplier is insufficient).

  5. #5
    Member
    Join Date
    Oct 2003
    Location
    Liverpool
    Posts
    70
    Thanks
    0
    Thanked
    0 times in 0 posts
    the manual dont have these details in there and i have found an area were you can set the agp Mhz
    so i've left that@66 atm...

    when i get a chance ill look into how my board works,

    cheers ears

  6. #6
    Member
    Join Date
    Sep 2003
    Location
    Calcutta, India
    Posts
    102
    Thanks
    1
    Thanked
    0 times in 0 posts
    Where in the Bios did you find this setting ?

    Vijay

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •