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Hyperthreading problems

I recently purchased many P4 HT enabled machines in order to further development within the company. However, to my dismay, the HT technology caused multiple problems and I'm about ready to send the computers back to dell and get some non-HT boxes.

The problem can easily be duplicated by going to the command prompt and accessing the rsh file within system32 to connect to a remote server. After executing whatever command, the process ends but doesn't exit back to the prompt.

Is there a patch or something that would fix this?? If it is possible, an answer would GREATLY be appreciated ASAP. Please send all comments to


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4 Replies
Thanks for your post Karl. Sorry to hear you are experiencing problems.

Hopefully the software community can help you with some ideas. I would also recommend you take a look at the hardware developer area of Intel's website for some assistance:

Black Belt
Karl -

Besides searching the Intel Developer Services site, you might peruse the Microsoft website, or, if a third party wrote the rsh application, look over their site for more information or fixes to your problem.

In addition, if you have access, you should report the problem through the Intel Premier Support site ( If this problem has been seen and reported before, they will be able to advise you on fixing it. If this had not been seen, the support technician will be able to locate someone that might be able to find a solution or would know how to go about finding a fix for you.

Hope you can get this problem solved soon.

-- clay
Black Belt
I got a personal reply from Karl that gave some more details on the "solution" to his problem. I asked him to post that here, Karl said he would, and then there was the system shutdown. So, let me post what Karl wrote about this.

Thanks for getting back to me about the hyperthreading issue.
Unfortunately (as advised by a microsoft posting), on computers faster than
3.00 Ghz running hyperthreading, some applications will fail to run or have
unexpected fatal errors. This apparently is the case with our application.
The end result is that we have to run the computers and swap them for non-HT
enabled computers. I'm rather surprised that this issue hasn't been formally
discussed or fixed given that HT technology has been around for more than a
year. Additionally, 95% of all computers now are being made to support it by

If anyone has any more details on this issue, please post them here. Is there some class of applications that are affected or some operating system services that don't work as expected at high processor speeds with HT on? Where was the Microsoft posting that detailed this information?

-- clay

This probably comes too late (3 months?), but Dell computers (many, anyway) allow you to disable HT in the BIOS. Although the non-HT boxes may be slightly cheaper than the HT's, when you figure your time to boxthe returns backup, re-build the order for non HT's, perform return return, wait for replacements to arrive, receive replacements, set up, etc., you will probably save money just keeping the HT boxes and disabling HT.

Also, unless there is a known bug in HT implementation, the problem is just as likely with the Windows code itself - like a timing problem(s) with block/resume processing that the code 'gets away with' on slower or non-HT processors (since only 1 thread can be running at a time in non-HT, the 'contention' is removed by definition, and the problem situation is therefore either 'impossible', or at least extremely rare).

Hopefully, if this is actually aWindows code problem, it will one day be corrected and you can then just turn HT back on??