Vista - VPC video output sometimes hangs for a moment

Hello,

I have been using VPC successfully on a desktop PC for years (see below
"Host 1"). The old system is to slow for current software, and so I
bought a faster system (see below "Host 2"). It has a high processor
clock frequency (3.16 GHz) because VPC can only use a single core. Now
my stuff in VPC runs about 2 to 4 times faster.

But I now got an effect I already saw on a notebook before (see below
"Host 3"). Sometimes - more or less often - the video output of the VPC
stops. The screen is refreshed significantly later. I can type a full
word (5-6 characters) into the VPC without seeing it.

Another symptom: The cursor of the Windows command prompt (CMD.EXE)
inside the VPC does not blink steadily all the time as it does on the
host system. Sometimes it stumbles.

This is extremely disturbing when typing or even deleting text. I want
to get rid of it.

It did *not* help to disable the second core of the new system. Although
both old and new system then run on a single core with hyper-threading.

All systems have onboard graphics. Event my old system. Nevertheless, a
colleague at work supposes that it could help to install a separate
graphics card.

Has anyone else experienced this problem and solved it?

TIA, Markus

***** System details: *****

Host 1 (old desktop PC):

Processor: Intel Pentium 4 (3.0 GHz)
Video: Intel 82915G/GV/910GL Express Chipset (onboard)
RAM: 2 GB
OS: MS Windows 2000 SP4

VM behaviour: Ok

Host 2 (new desktop PC):

Processor: Intel Intel Core 2 Duo E8500 (3.16 GHz)
Video: Intel Q45/Q43 Express Chipset (onboard)
RAM: 2 GB
OS: MS Windows XP SP3

VM behaviour: Video output hangs sometimes

Host 3 (a notebook):

Processor: Intel Pentium Dual T2330 (1.6 GHz)
Video: Intel R965 Express Chipset (onboard)
RAM: 2 GB
OS: MS Windows Vista SP1

VM behaviour: Video output hangs often

Virtual Machine on each host:

RAM: 512 MB
OS: MS Windows 2000 SP4

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