User:NeoAmsterdam/Overclocking: Difference between revisions

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(This deserves its own page instead of being stuck in my notes-to-self)
 
(Expanded, cleaned up, and benchmarked.)
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This is the same information you'll find in the [[Custom bootloader#overclock|overclocking section]] of the [[Custom bootloader|custom bootloader page]], but a little more elegantly and legibly than what <tt>[[:Template:Overclocktable|<nowiki>{{</nowiki>Overclocktable}}]]</tt> produces.
This is the same information you'll find in the [[Custom bootloader#overclock|overclocking section]] of the [[Custom bootloader|custom bootloader page]], but a little more elegantly and legibly than what <tt>[[:Template:Overclocktable|<nowiki>{{</nowiki>Overclocktable}}]]</tt> produces.

Note that this table omits the 216MHz bus setting - please refer to <tt>[[:Template:Overclocktable|<nowiki>{{</nowiki>Overclocktable}}]]</tt> for those settings.

= Overclock Settings =
The default setting is highlighted in <span style="background: rgb(80%,100%,80%);">green</span>.
<table class="wikitable" style="font-family: monospace; background: white; text-align: center;">
<table class="wikitable" style="font-family: monospace; background: white; text-align: center;">
<tr style="font-weight: bold; background: rgb(80%,80%,80%);">
<tr style="font-weight: bold; background: rgb(80%,80%,80%);">
Line 72: Line 77:
</tr>
</tr>
</table>
</table>

For the record, I altered my <tt>/boot/olpc.fth</tt> for 500MHz on a 200MHz bus (<tt>5dd</tt>) and I've had no complaints since.
= CPU-to-Bus Ratios =
The default setting is highlighted in <span style="background: rgb(80%,100%,80%);">green</span>.
<table class="wikitable" style="font-family: monospace; background: white; text-align: center;">
<tr style="font-family: sans-serif; font-weight: bold; background: rgb(90%,90%,90%);">
<td>CPU</td>
<td colspan="4">Bus Speed</td>
</tr>
<tr style="font-family: sans-serif; border-bottom: thin solid black;">
<td></td>
<td>133</td>
<td style="background: rgb(90%,100%,90%);">166</td>
<td>200</td>
<td>233</td>
</tr>
<tr>
<td style="font-family: sans-serif;">333</td>
<td>2.5</td>
<td style="background: rgb(90%,100%,90%);">2</td>
<td>1.666666</td>
<td>1.428571</td>
</tr>
<tr>
<td style="font-family: sans-serif;">366</td>
<td>2.75</td>
<td style="background: rgb(90%,100%,90%);">2.2</td>
<td>1.833333</td>
<td>1.571428</td>
</tr>
<tr>
<td style="font-family: sans-serif;">400</td>
<td>3</td>
<td style="background: rgb(90%,100%,90%);">2.4</td>
<td>2</td>
<td>1.714285</td>
</tr>
<tr style="background: rgb(90%,100%,90%);">
<td style="font-family: sans-serif;">433</td>
<td>3.25</td>
<td style="background: rgb(80%,100%,80%);">2.6</td>
<td>2.166666</td>
<td>1.857142</td>
</tr>
<tr>
<td style="font-family: sans-serif;">466</td>
<td>3.5</td>
<td style="background: rgb(90%,100%,90%);">2.8</td>
<td>2.333333</td>
<td>2</td>
</tr>
<tr>
<td style="font-family: sans-serif;">500</td>
<td>3.75</td>
<td style="background: rgb(90%,100%,90%);">3</td>
<td>2.5</td>
<td>2.142857</td>
</tr>
<tr>
<td style="font-family: sans-serif;">533</td>
<td>4</td>
<td style="background: rgb(90%,100%,90%);">3.2</td>
<td>2.666666</td>
<td>2.285714</td>
</tr>
<tr>
<td style="font-family: sans-serif;">566</td>
<td>4.25</td>
<td style="background: rgb(90%,100%,90%);">3.4</td>
<td>2.833333</td>
<td>2.428571</td>
</tr>
</table>
= Trials =
This table shows the approximate time in seconds it takes for the XO to display the "<tt>Welcome to OLPC!</tt>" message during the boot sequence (or what happened instead of booting up). As with all benchmarks, this table does not necessarily translate into real-world applications '''and''' your mileage will vary.

Settings highlighted in <span style="background: rgb(100%,80%,80%);">red</span> indicate settings that rendered the XO unbootable; <span style="background: rgb(100%, 90%, 80%);">orange</span>, bootable but unstable; <span style="background: rgb(80%,100%,80%);">green</span>, default.

<table class="wikitable" style="font-family: monospace; background: white; text-align: center;">
<tr style="font-family: sans-serif; font-weight: bold; background: rgb(90%,90%,90%);">
<td>CPU</td>
<td colspan="4">Bus Speed</td>
</tr>
<tr style="font-family: sans-serif; border-bottom: thin solid black;">
<td></td>
<td>133</td>
<td style="background: rgb(90%, 100%, 90%);">166</td>
<td>200</td>
<td style="background: rgb(100%, 90%, 90%);">233</td>
</tr>
<tr>
<td style="font-family: sans-serif;">333</td>
<td>12.404625</td>
<td>12.982728</td>
<td style="background: rgb(100%, 90%, 80%);">12.156...</td>
<td style="background: rgb(100%, 80%, 80%);">Invalid Opcode</td>
</tr>
<tr>
<td style="font-family: sans-serif;">366</td>
<td>12.088455</td>
<td>12.289983</td>
<td>12.202338</td>
<td style="background: rgb(100%, 80%, 80%);">Invalid Opcode</td>
</tr>
<tr>
<td style="font-family: sans-serif;">400</td>
<td>12.185320</td>
<td>11.716661</td>
<td>12.001534</td>
<td style="background: rgb(100%, 80%, 80%);">Invalid Opcode</td>
</tr>
<tr>
<td style="font-family: sans-serif; background: rgb(90%, 100%, 90%);">433</td>
<td>12.021018</td>
<td style="background: rgb(80%, 100%, 80%);">11.542834</td>
<td>11.428083</td>
<td style="background: rgb(100%, 80%, 80%);">Lockup</td>
</tr>
<tr>
<td style="font-family: sans-serif;">466</td>
<td>11.483150</td>
<td>11.728626</td>
<td>11.346144</td>
<td style="background: rgb(100%, 80%, 80%);">Lockup</td>
</tr>
<tr>
<td style="font-family: sans-serif;">500</td>
<td>11.713860</td>
<td>11.598526</td>
<td>11.138047</td>
<td style="background: rgb(100%, 80%, 80%);">Lockup</td>
</tr>
<tr>
<td style="font-family: sans-serif;">533</td>
<td>11.595032</td>
<td> 9.895351</td>
<td>10.949749</td>
<td style="background: rgb(100%, 80%, 80%);">Lockup</td>
</tr>
<tr style="background: rgb(100%, 80%, 80%);">
<td style="font-family: sans-serif; background: rgb(100%, 90%, 90%);">566</td>
<td>Restart</td>
<td>Invalid Opcode</td>
<td>Lockup</td>
<td>Lockup</td>
</tr>
</table>

Revision as of 22:36, 18 August 2010

This is the same information you'll find in the overclocking section of the custom bootloader page, but a little more elegantly and legibly than what {{Overclocktable}} produces.

Note that this table omits the 216MHz bus setting - please refer to {{Overclocktable}} for those settings.

Overclock Settings

The default setting is highlighted in green.

7de009e ### 4c000014 wrmsr
CPU Bus Speed
133 166 200 233
333 3d3 4d3 5d3 6d3
366 3d5 4d5 5d5 6d5
400 3d7 4d7 5d7 6d7
433 3d9 4d9 5d9 6d9
466 3db 4db 5db 6db
500 3dd 4dd 5dd 6dd
533 3df 4df 5df 6df
566 3e1 4e1 5e1 6e1

CPU-to-Bus Ratios

The default setting is highlighted in green.

CPU Bus Speed
133 166 200 233
333 2.5 2 1.666666 1.428571
366 2.75 2.2 1.833333 1.571428
400 3 2.4 2 1.714285
433 3.25 2.6 2.166666 1.857142
466 3.5 2.8 2.333333 2
500 3.75 3 2.5 2.142857
533 4 3.2 2.666666 2.285714
566 4.25 3.4 2.833333 2.428571

Trials

This table shows the approximate time in seconds it takes for the XO to display the "Welcome to OLPC!" message during the boot sequence (or what happened instead of booting up). As with all benchmarks, this table does not necessarily translate into real-world applications and your mileage will vary.

Settings highlighted in red indicate settings that rendered the XO unbootable; orange, bootable but unstable; green, default.

CPU Bus Speed
133 166 200 233
333 12.404625 12.982728 12.156... Invalid Opcode
366 12.088455 12.289983 12.202338 Invalid Opcode
400 12.185320 11.716661 12.001534 Invalid Opcode
433 12.021018 11.542834 11.428083 Lockup
466 11.483150 11.728626 11.346144 Lockup
500 11.713860 11.598526 11.138047 Lockup
533 11.595032 9.895351 10.949749 Lockup
566 Restart Invalid Opcode Lockup Lockup
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