HT is a CPU feature, but it must be supported by the BIOS to be of use.

These are old machines, but the E310 has some upgradability: you can bump up the memory to 4gb; you can add a PCI Express video card; you can add a Solid State Device for use as a boot drive; and you can configure it with a 64-bit operating system.

The E310 has HT already but I  want to up the CPU to what ever is the max. it will take, and the same with the 8300. I already have the 8300 at 4GB RAM and will upgrade the E310 RAM too.

I was wanting to know if the P4 3.4 HT is the fastest CPU that I can put into the 8300.

I also would like to know what is the fastest CPU that will go into the E310 (3100).

Lastly, how can I check the BIOS in the GX260 to find out if it will support HT?

I can't afford a new system but I can afford a $4.50 CPU for now. If you'd like to purchase me a "modern" system, I'd be more than happy to live up to your standards.

rdunnill - thanks for the help, I'll look into those, I have done just about everything to computers before except mess with the BIOS.

A quick check suggests that the best CPU supported by the E310 is the Pentium 4 640. I can confirm that despite what the documentation says, the E310 will support 4gb of G.SKILL PC6400 memory.

Update the GX260 BIOS to the latest version, and then look for hyperthreading settings. If you don't see them, the BIOS likely doesn't support hyperthreading, not that it made a big difference anyways and in some cases was counterproductive.

I'm not sure about the best CPU for the 8300, but note that some CPUs may require a different heatsink (made of copper rather than aluminum). 

Edit: See this thread for more discussion as to CPUs validated for the E310.

none of those systems are worth the money to upgrade.  I would save your money from all these upgrades and buy an inexpensive modern system

You're welcome. Regarding the BIOS, a bootable floppy is a good way to perform upgrades; I'm not sure if any of these can boot from a USB stick.

Regarding the E310/3100, I have one that I use to test upgrades. Mine was modded with the Startech PCI x1-to-x16 adapter, which allows the use of low-profile PCIe x16 cards like the Sapphire 6450.

The 8300 will boot from a USB, I have done Linux Pocket Rocket on it in the past. The GX260 has a floppy but the E310 does not; however, if needed I can add one some how.

I am going from P4 3.0 HT to 3.4 HT on the 8300.

I am going from P4 2.8 HT to 3.2 HT on the 3100 (as per your suggestion).

I'd like your suggestion on the CPU for the GX260 SFF, I'd like HT, it has a P4 2.4 non-HT. I'm not sure about other computers but when I turn HT off on my 8300 it is slow as dirt.

How do you look up all those specs for a CPU and what it can be upgraded to? The Dell manual is very basic.

I'm not sure, but some of the forum Rockstarts are very knowledgeable about such things. I'll ask them to step in.

Fastest CPU for the GX260 is a 3.06 Ghz Northwood SL6PG No prescotts.  GX260 WILL f12 BOOT from USB as will the dimension 3100 with the latest Bios.  Same for the E310  once bios is updated you may require to use the Rear ports because the front ports only put out 100 ma not 500 ma full current.They sell the GX260 with 3.06 w/HT on later versions.  EARLY 2003 Motherboards do not support HT or the 533mhz fsb.  For those the max is 2.8 ghz Northwood.  The 8300 might be too old for usb booting but updating the bios and checking F12 with a bootable stick will tell.  So SL7EY would work with all of them.

SL7PP for the 3100 I would think is max.  Chris M would have to verify that but It WONT work for the GX260 or the 8300.

NOTICE: Be careful not to bend any of the pins when you remove the microprocessor from the socket. Bending the pins can permanently damage the microprocessor.

BIOS - BIOS

Description	Importance	Version	Released	Supported OS	Download
Dell Dimension System BIOS, A04 Dimension 3100/E310 A04 System BIOS	Optional	A04	4/24/2006	BIOS

Description	Importance	Version	Released	Supported OS	Download
Dell OptiPlex System BIOS, A09 Optiplex GX260 A09 FlashBIOS	Optional	A09	2/1/2005	BIOS

Description	Importance	Version	Released	Supported OS	Download
Dell Dimension System BIOS, A07 Dimension 8300 A07 System BIOS	Optional	A07	10/1/2004	BIOS

Dimension 8300 Technical Specifications

SL6PG

I am really scared to alter the BIOS, mostly in part to never having done it before at all. Would I be able to back-up the BIOS? How do I change the BIOS? Should I just try to install the CPU(s) first and then update the BIOS if they don't work?

I'd still like a resource where I can look up mother boards and the CPU so that I don't have to keep asking for each one.

The E310 is my test work station, do I will be attempting to learn from it first.

Okay, thanks.

This is what I have found, will either one work in my 8300? BTW, the BIOS is currently A05 and a 3.0 P4 HT CPU. I know it also has an 800 FSB, I remember that when I bought it new years ago.

Intel Pentium 4 Processor 3.40 GHz 1M Cache 800 MHz FSB SL7PY 3.4/1m/800 #50

Intel Pentium 4 Processor 3.40 GHz 1M Cache 800 MHz FSB SL7J8 3.4/1m/800 #3

Which one should I get for the Dimension 8300? They are only $4 each.

This is what I have found, will either one work in my 8300? BTW, the BIOS is currently A05 and a 3.0 P4 HT CPU. I know it also has an 800 FSB, I remember that when I bought it new years ago. Intel Pentium 4 Processor 3.40 GHz 1M Cache 800 MHz FSB SL7PY 3.4/1m/800 #50 NO this will not work in an 8300 due to being Hyper-Threading technology AND Socket type Socket 775 (LGA775)MAY Work in the E310 CPUID 0F41h Intel Pentium 4 Processor 3.40 GHz 1M Cache 800 MHz FSB SL7J8 3.4/1m/800 #3 NO this will not work in an 8300 due to being Hyper-Threading technology AND Socket type Socket 775 (LGA775)CPU ID NOT Matching working processor in E310 (BIOS) CPUID 0F34h Which one should I get for the Dimension 8300? They are only $4 each.

Neither Works Because the Dimension 8300 cpu has 478 PINS it is NOT LGA  775 

Part Number(s): F4421/ 0F4421 3.4GHZ Processor (NW) For Dell Computers

Category: Internal Parts And Assemblies

Sub Category: Processors (CPU)CPU Speed: 3.4GHz

Bus Speed: 800MHz

Cache: 1MB

Package Type: 478 pin PPGA

Man Tech: 90 nm

Part Number F4421/ 0F4421 compatible with the following Dell Models:

Dimension 4600 MMT, Dimension 4600i, Dimension 8300, Inspiron 9100, Inspiron XPS, PowerEdge 700, PowerEdge 750

Wow, this is very confusing for me, we should take this one at a time. I'd like to do the 8300 first. I only use this computer for Netflix and it is connected to my 46" LCD HDTV as the second monitor.

So, this is what I am looking for (below)? If so, don't I have 32 bit now and what will 64 bit do to all my programs?

Part Number(s): GD037/ 0GD037 Processor Unit (P4 64BIT 551, 3.4GHZ, 800FSB, 1MB, SOCKET-T, E0) For Dell Computers   SL8J5 SL8PS SL9C

Thanks!