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Sounds like Pentiums with HT support. Each of those will show up in top as a pair of CPU's.
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Sounds like Pentiums with HT support. Each of those will show up in top as a pair of CPU's.

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What can I do about this, and will it cause a problem?
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What can I do about this, and will it cause a problem?

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Well, it depends on the definition of a problem. &nbsp;In the majority of situations, having Hyperthreading turned on is a good thing. &nbsp;There are, however, situations where it can apparently slow things down. &nbsp;For example, if you have a computationally intensive process that takes 1 minute on given processor with hyperthreading turned off, you might be able to get two processes done on the same processor in a minute and half. &nbsp; Note that the overall throughput has increased, but each individual thread took half again as long. &nbsp;Should this cause a problem for you, there is usually a BIOS setting you can use to turn of Hyperthreading.
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Well, it depends on the definition of a problem.  In the majority of situations, having Hyperthreading turned on is a good thing.  There are, however, situations where it can apparently slow things down.  For example, if you have a computationally intensive process that takes 1 minute on given processor with hyperthreading turned off, you might be able to get two processes done on the same processor in a minute and half.   Note that the overall throughput has increased, but each individual thread took half again as long.  Should this cause a problem for you, there is usually a BIOS setting you can use to turn of Hyperthreading.

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I was running a RedHat9 server with a single processor.<br />
I popped in a second processor as the board supported 2<br />
and upgraded the kernel from kernel-2.4.20-8.i686.rpm to <br />
kernel-smp-2.4.20-8.i686.r<wbr />pm <br />
I adjusted Grub to recognize and boot from the new kernel.<br />
I rebooted the system, ran &quot;top&quot; and now for some reason the server <br />
see's 4 processors listed. <br />
Any idea's? 
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I was running a RedHat9 server with a single processor.
I popped in a second processor as the board supported 2
and upgraded the kernel from kernel-2.4.20-8.i686.rpm to 
kernel-smp-2.4.20-8.i686.rpm 
I adjusted Grub to recognize and boot from the new kernel.
I rebooted the system, ran "top" and now for some reason the server 
see's 4 processors listed. 
Any idea's? 

SMB processor on RH9, I have a dual processors but top suggests that I have 4 processors

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