Concerning PCI-Express cards

tmbllama

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I am really wanting to upgrade to a Geforce 8600 GT today, but before I purchase the card and the power supply I need to have a couple of things clarified so that I don't dig myself in too deep. By the way, the rest of my computer is up to par for my needs (x2 AMD Athlon-64 4200+, 2GB RAM, 500GB HD).

First off - My current computer is a pre-built using a Foxconn MCP61SM2MA motherboard with onboard video (nVIDIA nForce 6100-405). Needless to say, my games run like crap.

I know the motherboard definitely has a PCI-E x16 slot. The following link details the specifications of my motherboard: http://gogofan.com/gogofannew/product_info.php?products_id=1162

"Slots: 1x PCI-Express x16 Slot (Runs on x8)".
That brings me to my first question - What exactly does "Runs on x8" mean? Can I still use the 8600 GT (a PCI-e x16 card)? Will it simply run at half of its' capacity?

Also, I think I remember reading on system requirements of the 8600 GT that it requires the PCI-E slot to be "2.0"? Well, I have been researching for hours on end (also tried a few different programs) and I can not find anything that tells me whether my PCI-E slot is 1.0, 1.1 or 2.0. If it IS only 1.0 or 1.1, will I still be able to use this card?

And lastly, since I do believe (according to GPU-Z) that the onboard video my mobo uses is PCI, will I have any trouble switching over to PCI-E from PCI? Any precautions that need to be made? I'm on a very tight budget as well, so I can't afford a top-of-the-line power supply. Would a 500W Thermtake PSU suffice in this case? Because that's about all I can afford.


Thank you so incredibly much for taking the time to read and reply to this post. And help given will be tremendously appreciated, seeing as how I'm no computer guru and don't really have anywhere else to turn to for this info. Thanks a million and a half, I owe you :wahoo:
 

merlinbadman

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Runs on 8x refers to the backwards compatability with older PCI-e graphics cards, your 8600GT with run fine. Which links to your next question.

PCI-e x16 slots are PCI-e 2.0
PCI-e x8 Slots are PCi-e 1.0

To reiterate, PCI-e x16 slots are fully compatible with older x8 cards.

I dont know why GPU-Z is telling you that your onboard grphics is PCI, unless it uses the PCI bus?? Im not familiar with onboard graphics or sound, but there should be no problems moving from onboard to dedicated graphics, provided you have a PCI-e slot (which you say you have).
 

michiganteddybear

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incorrect on the x8/x16 there merlin....

x16 (runs at x8) means you can fit an x16 card (physically), but electrically it only has 8 channels (x8). just about all pci-e cards will run ok in an x8.

the x8/x16 has NOTHING to do with pci-e 1.0/2.0.. it only referrs to the size and electrical connections
 

tmbllama

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Thank you for the fast replies! So the 8600 GT should be compatible with my motherboard then? What about the requirement for the card that states it requires a PCI-E 2.0 slot? I have no idea whether or not what I have is 2.0 or not, but I'm assuming it's not. I believe I read somewhere that you don't actually need a 2.0 compatible PCI-E slot to use the card. That is the thing that I'm most confused about.
 

atomiktoaster

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PCI-E uses a number of individual lanes to move data. with 2.0, each lane operates twice as fast as 1.0/1.1, so an 8x PCI-E 2.0 connection is about as fast as a 16x PCI-E 1.0 slot. Cards that support 2.0 are backwards compatible with 1.0 slots, they just use the slower speed (vice verse with 1.0 cards in 2.0 slots). With a graphics card, the PCI-E slot only needs to deliver as much data as the card can process, with faster cards needing bigger slots. With a card as slow as an 8800 GT you'll probably be fine even if you only have an 8x 1.0 slot. Are you sure you need a new PSU? 500W is a really a lot for this kind of setup. You might be fine with what you have. Also, check out the Radeon HD 4650. It's the current budget card of choice according to Tom's. Should beat an 8600.

http://www.tomshardware.com/reviews/best-graphics-card,2118-2.html
 

merlinbadman

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Yeah you are right, I got confused with AGP 8x Doh! I stand corrected.
Sorry tmbllama for telling you crap.
 

tmbllama

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Thank you so much for the reply, that was very helpful. My current PSU is 300W. I had a Radeon HD 2400 Pro (which I believe recommends 350W) and I was noticing framerate drops OVER my onboard graphics - which is not good. What wattage would you recommend? And thanks for pointing out the HD 4650, I will consider that.

@ Merlin - no worries bud :) You weren't intentionally giving me false info, I appreciate the response either way.
 

atomiktoaster

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Check out this article.

http://www.anandtech.com/casecoolingpsus/showdoc.aspx?i=3487

A high quality 350-450 W would probably be better than a 500 W PSU with lower quality components. With a low power budget GPU, and just a pair of drives you should be fine in terms of power consumption. The 300 W PSU you have is probably more of a worry because you don't know what sort of quality it is. The other factor is that newegg tends to move the rebates and discounts around the different wattage levels, so you might find a ~500 W PSU for cheaper, depending on the situation, which would be fine. Just be sure to check out the specific brand you buy, rather than just whatever the claimed wattage is. The bigger risk in my mind is a low quality PSU damaging your other components if it malfunctions, since your wattage needs are moderate.
 

Peaks

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All the 2.0 refers to is the version of PCIe the main difference being the amount of data that can be transferred at any one time (data rate)

1.0 - 250MB/s
2.0 - 500 MB/s

So I assume running a 2.0 card through a 1.0 supported slot would only allow half the capacity....but still work