• Vtcp.386 update for Win 95/98/98SE: Do I need it?
• Why the System.ini (IRQn=4096) trick doesn't work.

This update fixes three problems:

1) Unnecessary packet re-transmissions (i.e send/upload) in extremely high-delay satellite links.

2) Makes it possible to enable large window support (Scaling) so that TCP Receive Window (RWIN) can be set higher than 65535.

3) Makes it possible to activate Time Stamping.

If you are not on a satellite link or not one of the rare users who need RWIN > 65535, then you probably don't need this, but it does not hurt to apply it.

Go here if you use Win95, and here if you use Win98/98se, for the update.

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by DrTCP edited by redxii
last modified: 2009-10-24 02:30:59

The claim is that the tweak (IRQn=4096) improves network performance by allocating 4 megabytes of memory as a buffer for the IRQ (n) used by your network adapter. However:

• The setting has no effect on actual memory allocation.
  
  
• The setting does not actually affect network performance in carefully controlled tests. (Anecdotal reports are mixed and unreliable due to Internet and system variables, particularly the effects of caching.)
  
  
• There is no apparent evidence that there even is any such setting in Microsoft documentation.
  
• Windows does not allocate buffer memory for IRQs. (Buffers are the responsibility of device drivers, which allocate them by device, not by IRQ. On the PCI bus, a single IRQ can be shared by multiple devices.)
  

While it doesn't help, the good news is that (like TTL) this setting doesn't hurt (assuming you don't screw up your SYSTEM.INI file). Windows just ignores settings that it doesn't recognize.

reference

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by redxii
last modified: 2009-10-24 02:29:52