BIOS Hyperthreading question

[drewsaw2 3]

I went into the BIOS to disable hyperthreading and came across a surprise. I pulled my MOBO user's manual which clearly shows you how to do it through the Advanced CPU Features Page, but I don't see the option to turn off CPU multi-threading as it illustrates in the manual. As a matter of fact, I only see half of the options the manual says it supports. Beside the CPU multi-threading in the manual there is a little note that states: This item is present only if you install a cpu that supports this feature. uhh ?

[thefsxflyer 1]

The 2500K doesn't support hyper threading so no need to turn it off ;)

[drewsaw2 3]

Very good haha Cheers

[VirginAus737 0]

I had a chuckle when I read this, never mind, we all make mistakes.

[drewsaw2 3]

haha, not bad for a guy who can barely facebook. I was thrilled I even managed to get into the BIOS. I just thought it was a mystical place that only few could get in.

[VirginAus737 0]

especially with the classic BIOS in the Gigabyte boards.

[Swoop 0]

OK, now am confused. What's the difference between a hyper-threading and a multi-threading CPU (if there is one). For instance, my older Core i5-650 has two cores and two threads. Are the two threads considered hyper-threads, multi-threads? Also, in the BIOS there is also a config item that enables or disables mutli-threading. So which is what and what is which and should it be enabled for FS9 and/or FSX? Please advise and thanks!Mark

[VirginAus737 0]

Hyper threading just doubles your cores for some virtual cores. Not all apps will use hyper threading, its pretty new technology to the mainstream market. A thread is just like another name for a core I think and multi threading must just be like multi core.

[NGX 1]

I THINK:hyperthreading is the processor using virtual cores to help with the load. There are normally 2 virtual cores to every physical core. So 4 cores, 8 virtual cores. The virtual cores are addressed by the OS and basically shares the workload between each core, and it's own 2 virtual cores. Multithreading Is hardware support for the system to use more than 1 thread with one Core. So on a multicore system, it will allow multiple threads to be used per core instead of just one thread. So: HT off, MT on. HT is software based, MT is hardware based.

[Humpty 751]

HT was with the P4 , that is it wasn't a physical core . So during the P4 days if HT was enabled it would show up as two cores under device manager.

[VirginAus737 0]

I THINK: hyperthreading is the processor using virtual cores to help with the load. There are normally 2 virtual cores to every physical core. So 4 cores, 8 virtual cores. The virtual cores are addressed by the OS and basically shares the workload between each core, and it's own 2 virtual cores. Multithreading Is hardware support for the system to use more than 1 thread with one Core. So on a multicore system, it will allow multiple threads to be used per core instead of just one thread. So: HT off, MT on. HT is software based, MT is hardware based.

so if it is software, shouldn't an i5 2500k be able to support it if you can get your hands on the software.

[Humpty 751]

so if it is software, shouldn't an i5 2500k be able to support it if you can get your hands on the software.

Andrew why would anyone need Hyperthreading when it is useless in FSX and the i5 does not support it. As Di points out HT is software based and MT is hardware based FSX is needs "pure core" speed and HT would not offer that , correct me if I am wrong.

[VirginAus737 0]

Yeah I know, I am just saying if its software, why can't it be added. I wouldn't have a HT CPU unless the app I was using actually supported it.

[NGX 1]

Yeah I know, I am just saying if its software, why can't it be added. I wouldn't have a HT CPU unless the app I was using actually supported it.

No. Because it's set by the OS. Windows 7 supports HT. You already have the software. The 2500K does not support HT, so the OS cannot force it.

[VirginAus737 0]

So its still related to the CPU been able to support it. If I had a HT compatible CPU in Snow Leopard OS, I wonder if it would work?