XPS 420 and ATI 4870


An online group dedicated to connecting gamers of all levels -- especially levels you've beaten. Noobs welcome.

XPS 420 and ATI 4870

  • just about to recieve an ATI 4870 GPU from Saphire for a price so good I couldn't say no.


    My Current PSU is the Dell 375watt PSU, I've been doing some research and the 4870 only draw 2watts more than the Nvidia 880gtx at full load and dell used to stock the 8800gtx as an option with the dell xps 410 on the same PSU.


    Also, I will not be maxing out the card playing at 1650 x 1050 so I think I'll have enought head room to run the card perfectly, If not I'll uprgade the PSU so no big deal.


    My question is how will I connect the card to the dell?  It requires two PCIE power connectors, I only have one.  With the card comes a PCIe Y-Splitter and a molex to PCIE adaptor.  However the adaptor needs two molex and I only have one free plus a couple of SATA connectors.  Does the PCIe y-Splitter work, and give the same as using two idepent cables I think this is how Dell sold the unit with the 8800gtx.


    Can I use a SATA>Molex>PCIE


    Lastly, how many 12v rails does the Dell PSU have?

  • You can try it with the PCIe Y-splitter. I believe you are correct that this is how it was configured at the factory for video cards requiring 2 power inputs.

    That PSU has 2 12v rails from what I've been told internally. I think you should be fine.

  • Just an update, I have the 4870 working and running fine in my system.


    I used a molex splitter to proved me with two molex, the converted these to a six pin.


    I still intend to get a PCIE spitter, but struggled to find a UK seller, only US.



    Wanted to ask you a few questions regarding your post. I have been looking at the Radeon 4870 as an upgrade to my XPS 420.

    The problem I am facing is that I only have a 375w PSU and as far as I know it only have the one PCI-E powersupply. In your post you said you used a molex splitter to provide you with two molex. My XPS doesn't appear to have a molex as all my power cables are SATA.

    I wanted to know if you would elaborate upon how you achieved this ? I don't have any molex connectors. I assume that by molex you mean the four pin connector that are used to power HDD and DVD Drives.

    Thanks for your advice,


  • Just an update, I havel located my molex connector in my XPS system.

    On another note, i notice that to power a PCI-e cable you need to attach two Molex per PCI-E cable.

    Without tying myself up in knots with lots of molex splitters how did you approach this problem ?



  • I couldn't find a SATA to PCIE adapter, but I was able to find this:




    It may be a bit klugey to look at, but you could probably do the same thing the OP did with the addition of a couple of those adapters.

  • Are you running the 512mb or bigger!!!! Sorry, I must ask cause I'm looking for a new card for my 420 with the 375w psu too!!!!


  • Late reply, so may not be of any use.

     I ran the 512mb of ram on the 4870, with no problems, though now you might as well go for the revised 4890 which consumes less power.

  • I don't recommend you to run a 4870 with the 375W PSU.

    Of course the 4870 needs only 2W more then the 8800GTX, BUT if you've had ordered a 8800GTX, you'd have the 425W PSU.

    So, buy a new PSU before you're buying a new Graphics card.