My 530s has a ATI Theater 650 PRO Combo TV Tuner card and uses the short PCIe slot. Can I install a graphics card in the longer PCIe slot. I'm trying to use it as media center and connect it to HDTV through HDMI or component connection.
You will just need a "Low Profile" card since you have the slim case. You can use either PCI Express x16 or PCI Express x16 2.0 (backwards compatible) cards. Here is a link to some: http://www.newegg.com/Product/ProductList.aspx?Submit=ENE&N=2010380048%201069633099%201419530408&nam...
The above is for the newer PCI-E x16 2.0 cards but you can also look at the PCI-E x16 cards too: http://www.newegg.com/Product/ProductList.aspx?Submit=ENE&N=2010380048%201069609641%201419530408&nam...
Your current card is using the PCI-E x1 slot.
I have a concern over how many tuner card and graphics card can be supported by 530s (the little one). When I placed the order, I selected ATI tuner card. Then tried to select a graphics card, The webpage gave a message that PCIe slot has been taken. I was only able to select the graphics option in the motherboard. When I got the PC, I found out there are two PCIe slots, one long and one short, and ATI tuner card uses the short one.
Will the additional graphic card work with tuner card ?
Will the additional graphic card work with tuner card ? Yes.
The PCI-E x1 slot (short one) was initially designed for graphic cards but never really took off. Almost all graphic cards today use the PCI-E x16 slot (long one) above it. There are some devices such as your tuner card that use this slot but most other devices such as sound cards, etc. still use PCI. I don't know why it wouldn't let you configure the tuner card and a graphics card. When I attempted it, it worked fine.