HT bus
- Thread starter vice
- Start date
Socket 939 systems have a one way HTT bus of 1000 MHz. While Socket 754's have 800MHz one way.
When overclocking, either of these systems can get very unstable when passing that original threshold (1000 for 939, 800 for 754)
When overclocking either socket A64...most overclockers will suggest lowering the HTT multiplier to 2 or 3 just so that the HTT bus does not become a limiting factor when overclocking.
It adds a twist to traditional overclocking, but is easily overcome.
When overclocking, either of these systems can get very unstable when passing that original threshold (1000 for 939, 800 for 754)
When overclocking either socket A64...most overclockers will suggest lowering the HTT multiplier to 2 or 3 just so that the HTT bus does not become a limiting factor when overclocking.
It adds a twist to traditional overclocking, but is easily overcome.
FragTek
New member
This limiting factor also greatly depends on your motherboard... Some mobo's just don't like to clock higher than 1000 and is CRUCIAL to lower ur htt in order to achieve a stable overclock.
I didn't have to lower my HTT from 5 to 4 until I hit 265fsb and eventually had to work down to an HTT of 3 when running at 300mhz 1:1.
I didn't have to lower my HTT from 5 to 4 until I hit 265fsb and eventually had to work down to an HTT of 3 when running at 300mhz 1:1.
never let the hyper transport go over 1000 on 939's or 800 on 754's cause usually only a few MHz over these figures will cause instablity and so screw ur ocin!;
the hypertransport is bacically the connection to your non integrated (to southbridge) components includin the PCI bus (but not PCIe or AGP) so usually lowering the hypertransport speed has little impact on system speed (esp if the system is oced) unless your ht nus is saturated!
the hypertransport is bacically the connection to your non integrated (to southbridge) components includin the PCI bus (but not PCIe or AGP) so usually lowering the hypertransport speed has little impact on system speed (esp if the system is oced) unless your ht nus is saturated!
^^1200 not uncommon (u must have xcellent components and that processor must be exceptional go u!!)
^^1600 ?? usure thats not the 'ddr' speed cause its not that i dont doubt ya (i dont) but @ 2.5 given the fact that 1600 is equal to 3200 Mhz 'ddr' (a full 1200*/600 over what amd can make reliabily) so thats excessiviley high (but all rights u shouldnt b able 2 boot)
what i said were guidelines and given @ actual MHz not the ddr some quote
^^1600 ?? usure thats not the 'ddr' speed cause its not that i dont doubt ya (i dont) but @ 2.5 given the fact that 1600 is equal to 3200 Mhz 'ddr' (a full 1200*/600 over what amd can make reliabily) so thats excessiviley high (but all rights u shouldnt b able 2 boot)
what i said were guidelines and given @ actual MHz not the ddr some quote
as far as I can tell .... the rule of the thumb for ocing an athlon 64 is
Anything below 260 mhz FSB ( of HTT as people call it sometimes ) LDT speed should be 4x. Above that put LDT at 3x . It does not affect performance by much. U wont even feel the difference in performance. Just keep FSB x LDT value below or near 1000.
As in 260 x 4 = 1040 ( possible with a good board )
but 300 x 4 = 1200 ( NEVER possible )
thus 300 x 3 = 900 ( barely if any drop in performance )
Hope this answers ur question.
Anything below 260 mhz FSB ( of HTT as people call it sometimes ) LDT speed should be 4x. Above that put LDT at 3x . It does not affect performance by much. U wont even feel the difference in performance. Just keep FSB x LDT value below or near 1000.
As in 260 x 4 = 1040 ( possible with a good board )
but 300 x 4 = 1200 ( NEVER possible )
thus 300 x 3 = 900 ( barely if any drop in performance )
Hope this answers ur question.
Personally LDT bus is something i really dont get a rat's ass about as long as its 3x ( not lower ) . Real world performance has HARDLY , if any , affect with a lower LDT bus . Its on AUTO right now on my NF4 but A64 Tweaker tells me that its at 3x , so w/e the mobo feels best for its stability.
