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#11
I purchased and shipped a GT220 to member no longer on here and he seems to like how it preformed. So If your stuck on Nvidia I would recommend it based on his reviews on using it for not only gaming (mostly GTAIV) but photoshop and other GFX applications. It can be found on the Dell link.
But then XFX makes a single slot 5550 card but still requires a minimum 400w psu and no 6pin connector required it's pretty compact yet the shroud could still be a problem. Newegg.com - XFX HD-555X-ZNF2 Radeon HD 5550 1GB 128-bit DDR2 PCI Express 2.1 x16 HDCP Ready Video Card
You can also buy low profile bracket combos but after doing some searching I couldn't find a bracket combo that would work on any of the cards.
Newegg also offers a 5450 low profile card without a fan so it would fit but It didn't list the minimum power supply which I would presume to be 400w also Newegg.com - SAPPHIRE 100292L Radeon HD 5450 (Cedar) 1GB 64-bit DDR2 PCI Express 2.1 x16 HDCP Ready CrossFireX Support Low Profile Ready Video Card
Unfortunately these are the problems commonly found when trying to upgrade an OEM system. Most make it so your stuck going back to them to get any kind of upgrade.
Fabe