This page is a wiki. Please login or create an account to begin editing.

Startup Doubler

Your rating: None Average: 4.4 (5 votes)
Year released:
[www].se [ftp].se [mirror].us [mirror].de
StartupDoubler272.sit_.bin (114.88 KB)
MD5: 3914a0f206aa5e9b832886044646fb67
For System 7.0 - 7.6 - Mac OS 9
[www].se [ftp].se [mirror].us [mirror].de
Startup-Doubler.sit (51.89 KB)
MD5: 43e164d4b47d6d97835b3184f2305945
For System 7.0 - 7.6 - Mac OS 9
[www].se [ftp].se [mirror].us [mirror].de
Startup_Doubler_1.1.sit_.hqx (123.15 KB)
MD5: e72d7dbfde49a5aa466d1d4e0d44d017
For System 7.0 - 7.6 - Mac OS 9
This app works with: SheepShaver,

Startup Doubler's software acceleration compensates for less-than-optimal disk performance to make extensions, control panels, the Finder and startup apps load faster.

- Zap through startup icons!

- Save time each time you startup your Mac!

- Startup your PowerBook/iBook faster at airports (and everywhere else, too!)

Waiting too long for your Mac to start up, day after day, only adds up to a lot of wasted time. Startup Doubler can help: expect pre-G4 Macs to startup 10% to 50% faster, depending on disk speed. Fast disks in the latest high-end Macs, however, can't be accelerated much, so if you have one of those you probably won't notice much difference.

Before you install, please make sure to check your disk with Disk First Aid or a similar utility. Minor disk errors that may have gone unnoticed before are sometimes made apparent when Startup Doubler is installed. Common such conditions and fixes for each are detailed on the Frequently Asked Questions FAQ page.

New in version 2.7.3

01/17/03: v.2.7.3 fixes a freeze bug that would sometimes happen when the *Startup Doubler Extension grew larger than 500K. This version is also slightly faster than previous ones.

Info from Now it's FREEWARE.

I found it when I browsed archived from 1999.

First download: v2.7.2
2nd download: v2.7.3
3rd download: v1.1

Architecture: PPC

Startup Doubler works on Macs running Mac OS 7.0 through 9.2.2


WhosIt.There's picture
by WhosIt.There - 2016, September 11 - 7:00am

The two extansions have very different purposes.

Startup Doubler speeds up the loading of the extensions during startup (all those icons that appear across the bottom of the screen). That's it. It doesn't do anything else once the computer has started up. From a vague memory, it basically caches the extensions and reloads them all as a whole, rather than individually ... but I may be remembering wrong.

Speed Doubler speeds up the actual some aspects of the usage of the computer after it has finished starting up.

They should be compatible with each other (and with RAM Doubler).

3371-Alpha's picture
by 3371-Alpha - 2016, September 11 - 5:02am

I wonder what's the difference between this & Speed Doubler, or if they're even compatible.

mrdav's picture
by mrdav - 2015, March 28 - 1:28pm

Oh, I see. It is in the external link. Sorry, I was looking at the internal server dLs

Laurier's picture
by Laurier - 2015, March 28 - 6:48am

Added vertion 2.7.3 freeware.

bertyboy's picture
by bertyboy - 2011, April 5 - 11:11pm

Hmmm. Am I sceptical ? Even without this my IIci used to boot about as fast as my Mac Pro does now. Maybe it's aimed at those with Extension overload.