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CTU - Central Tweaking Unit

Welcome to CTU! (Central tweak utility)

With the death of DOS many users require a tool to either simply ensure certain settings are set with their CPUs or also to tweak them for more performance.

CTU was developed for this very purpose.

Features:

•	Enables all performance related settings under Windows 9X/and WinME.

•	Allows settings “on-the-fly”, no need to reboot

•	Recommended settings and documentation

FAQ:

Q. Does it run under Windows NT or Windows 2000?
A. No, not yet. With time (and money) it will!

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Q. What are the best settings?
A. Click the ? in the upper right-hand corner and then click on an option. A recommended setting will appear.

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Q. What CPUs are supported?
A. All of AMD’s K6 series (K6, K6-2, K6-III), including the rare K6-2+ and K6-III+.

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Q. Does it work with other CPUs?
A. Not yet. We need documents, technical sheets and money to add more CPUs to the supported list.

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Q. I enabled XYZ and the computer freezes up, why?
A. Well you are accessing the very heart of the computer. Compare it to open heart surgery. If it didn’t work, it probably never will.

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Q. Will other languages be supported?
A. Between us we can do Dutch, German, French and English. Anything else we need a translator for!

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Q. Why do I need this if I’m using DOS tools?
A. Because you have to reboot for many of those tools to work and it’s more “intuitive” under Windows.

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Q. I don’t think the description of XYZ is good.
A. Fine. Send it to us, we’ll change it if it’s correct.

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Q. Is it safe to change the CPU features on the fly, doesn’t it decrease stability?

A. A special test version of CTU that switched between the fastest and the slowest (L1 cache enabled)  settings with a delay of 0.1s between the switches was active while running the benchmark 3DMark2000. While benchmarking CTU switched settings over 3600 times. This did not cause any stability issues.

Note: the system scored 379 3Dmarks.

Command line parameters

CTU also consists of a small and fast command-line only version (ctuclwin.exe). This program can fully configure the CPU with command-line parameters. This small version is used automatically when you use the ‘auto apply at windows startup’ feature to increase boot speed.

Write Allocation

/WA [WALimit] [WA1516MB]

WALimit is the Write Allocation limit in MB.

WA1516MB: 1 if you want Write Allocation for the 15-16MB range, 0 if you don’t

L1 cache

/L1 [0/1]

0 : disable

1 : enable

L2 cache

/L2 [0/1]

0 : disable

1 : enable

Data Prefetch

/DP [0/1]

0 : disable

1 : enable

Write Combining

/MTRR0 or /MTRR1 [Start] [Size] [Type]

Start: start address (hexadecimal)

Size: one of the following values: 128kB, 256kB, 512kB, 1MB, 2MB, 4MB, 8MB, 16MB, 32MB, 64MB, 128MB, 256MB, 512MB, 1GB, 2GB, 4GB.

Type: N for Normal, W for Write Combined, U for Uncached.

Multiplier

/M [multiplier]

With multiplier any of these values: 2.0, 3.0, 3.5, 4.0, 4.5, 5.0, 5.5, 6.0

Write Ordering

/WO [0/1/2]

2 : No Write Ordering (fastest)

1 : All except UC/WC (fast)

0 : All (slowest)

Quit

/Q

This quits the program after applying the settings.

This parameter is only supported (and needed) by the GUI version of CTU.

If you are not sure about the parameters push the CLine button and look what CTU says about it.


Enable write allocation (read before write).

Recommended: Enabled


Write allocate limit.

Recommended: Fill in how much memory your system has


Enable write allocation for the 15 to 16MB memory range. Disabling only needed for some uncommon I/O adapters that use this memory range.

Recommended: Enabled, unless you experience problems


Enable the onboard L1 cache. If disabled this will cause an enormous performance hit.

Recommended: Enabled


Enable the onboard L2 cache.

Recommended: Enabled


Enable data prefetch. Speculative read

Recommended: Enabled


Enable write combining

Recommended: Do not change unless you know what you are doing

Note: Easy Write Combine setting is under construction


Start of the memory range

Recommended: Do not change unless you know what you are doing

Note: Easy Write Combine setting is under construction


End of the memory range

Recommended: Do not change unless you know what you are doing

Note: Easy Write Combine setting is under construction


Size of the memory range

Recommended: Do not change unless you know what you are doing

Note: Easy Write Combine setting is under construction


Type of memory.

Normal: normal memory

Uncached: uncached memory

Write Combined: write combine memory writes

Recommended: Do not change unless you know what you are doing

Note: Easy Write Combine setting is under construction


Multiplier

Use the slider to change the multiplier.

The multiplier controls the CPU clock.

Recommended: Use with care, setting the multiplier too high will crash your system.

Note: This only supported by the mobile K6-2+/III+.


Write Ordering

This controls the write ordering from writes to memory.

No Write Ordering: No write order is maintained. This is the fastest setting.

All except UC/WC: Write order is maintained for all writes except for writes to Uncacheable/Write Combined memory.

All: Write order is maintained for all writes. This is the slowest setting.

Recommended: No Write Ordering

Note: if your motherboard has no support for the #EWBE signal (used with synchronizing memory writes), which is common with uniprocessor (one CPU) systems it is safe to use No Write Ordering.


Auto apply the CPU settings at windows startup.

Recommended: Enable this if you want to apply the settings automatically at windows startup.

Note: the settings that are applied are saved in the profile Startup_Settings.


Select a profile and load it.

Recommended –

Note: The setings are not applied until Apply is pressed.


Save the current profile.

Recommended –


Delete the selected profile.

Recommended –


Apply the current settings.

Recommended –

Note: The program does not change any settings until you press this button.


Reads the current settings from the hardware and updates the screen.

Recommended –


Copies the current settings as command line parameters to the clipboard.

You can use this to easily set up the command line version of CTU.

Recommended –