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From: v081nhdb@ubvmsd.cc.buffalo.edu (Nina Banerjee)
Newsgroups: comp.sys.ibm.pc.misc
Subject: Switching a 4.77MHz 8088 for an 8Mhz V20
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Date: 5 Aug 90 17:29:37 GMT
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	It's no problem replacing an 8088 with a V20. But, you can't make the
V20 run at 8MHz unless you have an 8 Mhz motherboard.. Unless your motherboard 
has turbo, the V20 will run at 4.77MHz. Boards that run at 8MHz have two 
crystals, one running at a little over 14 Mhz for the 4.77MHz CPU clock,
and one at 24.000 MHz for the 8 Mhz clock. An 8 Mhz V20 is rated to run at
up to 8 MHz, it cannot run faster than the clock speed.
	As for the RAM speed, in an XT, for 4.77Mhz you need 200ns RAM,
8 MHz needs 150ns RAM, and 10 MHz needs 120ns RAM, since an XT has one wait
state.
				Nina Banerjee