At pricewatch.com the only 4200's I could find in that price range are 64 meg Ti4200s.
Probably worth the extra $25 for the 128 meg version (they go for $100 or so), but if all you have is $75 for a video card, the 64 meg Ti4200 is a great buy.
I don't think any games out right now offer a 128 meg texture set. And even the games that will have a 128 meg option in the next couple years will have a 64 meg texture set for people with 64 meg cards.
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<font color=red><b>Radeon 9500 PRO</b></font color=red> <i>(hardmodded 9500, o/c 322/322)</i>
<font color=red><b>AMD AthlonXP 2600+</b></font color=red> <i>(o/c 2400+ with 143 fsb)</i>
<font color=red><b>3dMark03: 4055</b></font color=red>