Normal idle temps in an XPS410 were 60-62c, load temps went up to 80c. By adding two 80mm exhaust fans on the back you can shave 10c off of that.

You can google Gainward ExperTool for overclocking and I believe gpu fan control. Up the gpu fan till the sound is noticeable( about 75%) and you should be able to take off a couple more degree's.

In addition to the Gainward ExperTool for overclocking suggested by contrvlr, the link below is for the new RivaTuner 2.1 overclocking tool and has the fan control as well.

 

 

http://downloads.guru3d.com/download.php?det=163

Interesting.  I was wondering how much my 8800gts (640mb) was underperforming due to my setup.  I idle at 54c and max has been 65c.  I'm still very happy with the card though.  Huge performance increase compared to a x800xt.

 

Dimension XPS Gen3
P4 550 HT 3.4GHz 800FSB
Win XP Home
2 GB Dual Channel DDR2 533
EVGA 8800 GTS 640mb
ForceWare 158.19
Dell Ultrasharp 1907FP
80GB SATA
SB Audigy 2 (D)
16x Sony DVD

My case is different, I run 61 at idle and can reach 90 at full load, and the alarm is set at 110. Just for precaution. I've seen  a huge spread of these temps. Your fine. But if you take the exaust advise it will help with cooler temps. You can add in several types of exhaust fans, from Pci slot ones to case mount, whatever you have room for.

 

XPS 600
XP Media Center 2005, dual boot Vista Ultimate
Pentium D 955 3.46 Ghz EE OC'able
2 Gigs DDR2 533 Mhz
640 Mb EVGA Geforce 8800 GTS
320Gig SATA primary,250Gig SATA secondary,160Gig SATA3rd,120Gig EIDE 4th backup
Avermedia MCE500 TV dual tuner
Creative XIFI Extreme Music
G5 Logitech Gaming mouse, Wireless Logitech Rumblepad 2
2007WFP

XPS M140
XP Media Center 2005
Pentium M 760 2.0 Ghz
2 Gigs DDR2 533 Mhz
60 Gig 7200 RPM drive

My 8800GTS runs at around 52-53C idle and around 63C load.   I followed convir advise and added 2x 80mm in the back of the case.    I dont know what my idle temp would've been if I didnt add those 2 exhaust fans since I got the fans before the card...  but they do push out good amount of air so...   I won't be surprised if my idle temp reach 64C idle without those fans on.

 

I just checked my temp...    it's at 50C