Xampp lite 1.7.3 Yslow issue

[RP_Joe]

Hello. I am new here.
I have an install of 1.7.3 installed on a win2000 box. It works well. I want to use it to test the speed of some code. On my developer machine I installed Firefox 4 with 3 plugins. Firebug, Yslow and page speed. WinXP sp2
I have turned off prefetch on Firefox.

It works great. But when I put several Html files on a folder and run them, I get different load times. One is a Html page with some text and a green background. Another has same content but a large picture. I hit Cntl F5 and it reloads. But the reload time if different every time. Sometimes its .750 others it 1.380, .990 .842 seconds.

I also installed a shopping cart and loaded 2 items.
Initial load time can be 8.350 seconds. cntrl F5 then its: 1.730, 2.580, 4.727.
By default the cache on Apache is commented out.
The only change I have made to the default install is in the PHP.ini file to allow error messages for deprecated code.

I don't understand why I don't get consistent readings. Any help would be appreciated. Thank you.

[RP_Joe]

I fixed this by turning off all cache in Firefox.