Noob attempting first upgrades

That HP is a fairly high-end rig. I'm not sure why you want to move parts to a new box.

http://h10025.www1.hp.com/ewfrf/wc/document?docname=c01...

Only 2 upgrades make sense to me:
A new, faster video card and a SSD.

With an HP 460 watt PSU, you should be able to run a fairly good card.
If you do go with a new motherboard and switch parts out, you will need a new copy of the OS.
If you keep the system and add a SSD, you can migrate the existing OS to the new drive.

Newf.

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The e9180t uses a Pegatron motherboard that is known to have several issues. I have definitely had some problems with this computer. It stops detecting wireless networks (often), it blue-screens (not very often), freezes randomly among other little quirks. It's never done anything that a reset hasn't fixed. After doing quite a bit of reading it seems many other people had these problems and it all pointed back to the mobo. The ASUS P6T looked like an affordable alternative to fit the i7 920.

However, the P6T is a full ATX board and as far as I know, the Pavilion Elite cases only hold microATX boards. I could be wrong, but from what I've read it's meant for the microATx Pegatron board (9.6"x9.6"?). It's also a very tight case with little ventilation.

I don't know enough to know if I'm just being paranoid about the mobo. It's never crashed on me in the middle of watching a movie or playing a game so I'm not sure if i'm overreacting. My other alternative, if I AM being paranoid is to just go straight to upgrading my GPU. But I'm not sure my 460W PSU will love my choices.

EVGA 650 Ti:
http://www.amazon.com/EVGA-Dual-Link-Graphics-01G-P4-36...

MSi HD 6850:
http://www.amazon.com/MSI-DisplayPort-PCI-Express-R6850...

First, that NVidia 650ti should work fine in your system.
It only needs 1, 6-pin connector which your box should have.
HP, (and Dell for that matter), use power supplies that while nothing special are not junk either.
From a hardware standpoint you should be just fine.

I would still try to get your system working like it should.
Yes, the original HP operating system has features different from the upgraded Win 7 download.
In this case though, making sure you have the most updated drivers, bios and a cleaned up OS may work wonders.
If Win7 64 bit drivers for your Pegatron are not available, Vista 64 bit ones will work but XP drivers do not.

To clean up the OS, I recommend CCleaner from www.piriform.com

There is no downside to trying this, as you can always throw in the towel and buy more parts later.

Newf.

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