Desktops General - Read Only

Last reply by 08-30-2010 Unsolved
Start a Discussion
3 Argentum

XPS 435T Observations and Answers (Power, Case, Misc)

Here are some answers to questions I had about the Studio XPS 435T that no one could answer prior to my buying it. Now that I have it, thought I would share

- The default 475 W PSU was able to run 3 SATA drives, 1 DVD writer, the i7 920 processor, a BFG OC GTX 275 graphics card (with two 6 pin connectors) and xfi titanium PCI-E card without problems. My battery backup with monitoring never showed a peak of higher than about 385W even when playing Fallout 3, all settings maxed with lots of screen action. The average usage outside of the game and using desktop apps was about 220W. I did a web-based calculator where you add up all your peripherals and it said it shouldnt peak higher than 387W. Additionally a graphics card with 2 6-pin connectors cannot pull more than 225W by itself. (75W for the PCI-E slot, and 75W for each 6 pin connector). The box for the graphic card said you needed 575W PSU with 42A on the 12V rail, but this is also just an estimation based on a system with a core i7 975 which means they are assuming everything enthusiast in the box, completely maxed out. I did have to use a different PSU, but not because the default one couldn't handle the setup.

- This has been covered here before, but I will give a concise summary: The default 475 W PSU is apparently very sensitive to having a perfect sine wave, so normal battery backups will not operate in backup mode with this PSU. (ie: pull the plug or shutoff the breaker, and the system resets and will not turn on while in battery backup mode). This is NOT an issue of slow switching to battery as the system will not turn on while there is no wall power, even when any of the batteries are fully charged. DELL apparently recommends the server grade battery backups which will run you 300-500$. I installed a Corsair HX620 power supply and it does not have the same problem. The original DELL 475W PSU would not work with either a 750VA or 1300VA APC battery backup, whereas the Corsair HX620 worked with both, the larger one lasting 21 minutes before shutdown and the lesser one lasting about 13 minutes before shutdown. The only problem with the new PSU is the physical size not matching the case. (see next item)

- The PSU that comes from dell is larger than a default PSU. It is almost square from the rear of the PC, whereas the new Corsair HX620 is almost rectangular, This causes 2 of the 4 screws to not line up on the PSU. (still installs tightly). This also leaves a gap of about 5" x 1/2" below the power supply where air can flow freely in/out of the case. This is less than ideal because dust isnt being directed through filters, etc. (maybe doesnt matter). I am going to the store tonight to see if there are any 3rd party power supplies with this larger form factor.

- The top case mic/headphone jacks include a standard cable that goes to any of the new sounds card. If you don't bundle a sound card, it plugs into the motherboard. This is a 10-pin connector very similar to the internal USB motherboard connectors. (the missing/blocked pin is in a different place so you dont mix them up). So if you wanted to buy a sound card after you received the machine, you can rest assured, you already have the part to hookup the jacks to the card.

- Something I missed in the design/tech specs but was pleased with is the machine has a builtin windows media center infrared receiver up next to the card readers at the top, and it is automatically detected and drivers installed with Windows 7 RC x64.

- This is more of a testament to Windows 7 than this machine persay, but I two 500GB drives in a mirror using the Intel Matrix Storage controller on my old XPS 410. I moved them to the new machine expecting to have to wipe, re-mirror and re-install the OS. Instead, the Intel Matrix Storage controller on the Studio XPS 435T found the existing mirror, had to rebuild it, but did so while the system was in use. Additionally on the first bootup of the existing Windows 7 x64 OS, a screen popped up with about 100+ "New Hardware Found" items on a list, it automatically installed drivers for everything. After one reboot, everything new was detected and I was up and running. I will probably reformat and reinstall when Windows 7 retail comes out.

- The glossy finish so far seems durable against scratching, but it does show fingerprints quickly. Keep a micro-fiber polishing cloth nearby and they dissapear quickly tho. I wish the top/front was the same metal with matte finish as the sides, because the white matte finish is fantasticly smooth and doesnt show any fingerprints. I even had the side door fall when I had the case open, it hit the leg of my chair and I was expecting a scratch or a dent, and the finish was undamaged.

- All my previous DELL's with the media card reader, the reader would "dissapear" from the system after a couple of weeks of uptime. A reboot or restart of the USB hub driver (sometimes hard to find in the device list) would cause it to be re-found. I have only had the Studio XPS 435T for a few days, so will have to see how it goes with this card reader. I normally just use the one in my 2408 LCd panel since every time I turn it off/on each night, its USB devices are redetected, so even if it were to disaapear, its much easier to bring them back.

- I never knew what flexbay was. In this machine, its really just 2 extra 3.5" drive bays that can be internal or external. There doesnt seem to be anything default that goes in there, so when you use the slide down front door, you are looking at two drive bay covers. The bays DO NOT need any kind of tray. They have tensions clips on one side and you screw in on the other side. Very solid and snug fit for hard drives. This means you can fit a good 5 hard drives without any special setup. Since nothing comes in the flexbays, the slide down front cover is a little of a let down, not sure if I will ever have anything front acessible there. Maybe a fancy temperature monitor or fan speed controller someday.

- There are 6 SATA ports, however 1 is used up by the eSATA port on the rear of the machine that is soldered to the motherbaord, so you cannot disable it to free the extra port. This leaves 5 usable internal ports. So if you want 5 hard drives and 2 optical drives (which all fit physically), you will need another SATA controller with at least 2 ports on it.

- There is no floppy controller on the motherboard, so you would need a USB floppy or install a controller. I am trying to resist the completionist urge to put one in.

- Even with all the default connections hooked up, there are still 2 more USB 2-port headers open on the motherboard, so y ou can easily have 4 more USB ports or hook up devices in the flex bay or CD bay that use a motherboard USB connection.

- Would have liked a front-panel firewire connection, rear only, but its minor, I only seldomly hookup my video camera to record from it.

- The case is silent with the default PSU. Even on startup it seems to not spin up the fans at all. The Core i7 920 with the default air cooler is running ambiently at about 49 degrees C, and under load about 60 degrees C. Supposedly 68 degrees C is where you want to stop for this proc. I imagine the fans start kicking on when you get close to 68C, but I haven't been able to get this to happen yet.

- The case appears to be a standard ATX case. Someday when the guts are obselete, it will be nice to try swapping them out. Even the front panel connections all seem to have specific headers to the motherboard that appear very standard. The PWR/RESET/HD light are in a single header, which appears that it might be a standard pinout, but even if its not, the wires are obvious and splitting them to the smaller jumpers would be easy. There isnt a fancy logic board inside the front bezel that makes this difficult like in prior dells. The system really feels like a very high quality build it yourself. The case is really heavy duty, very smooth, the engineering and manufacturing is top notch. If I was still building my own PCs, I would definitely buy this case if it was sold as a empty case.

Hope this helps you. I am very pleased so far. As long as I can find a PSU that matches the physical dimensions of the original part, but also works with a battery backup, I will have no complaints.

Replies (15)
2 Bronze
2 Bronze

well, I just read this review, thanks for the great details, I  didn't know about this PSU issue before I bought the xps 9000 a few months back, I could swear I tested with an APC 550 upon setup and everything was fine, but I just re-tested and realized that the UPS/PSU is not working, (I noticed couple of 'reboots' before but chalked it down to overheating, but now I'm sure they were power spikes/dropouts)a big issue for me since I could loose a lot of work if power cuts off before saving..


I'll contact Dell but I think is going to be a waste of time...

Is that PSU link above really comparable with the XPS 9000?


I checked their comparability tables and they do not mention the 9000 case AFAI can tell...

3 Silver


 Have had the XPS435T or 9000 same thing, for almost a year and the first thing changed was the power supply. For vid card upgrade

and added HD's and such. The 475W good PS but marginal if  big vid card i.e. 5870-5970/GTX285-295 and so on. Then overclocking it

adding drives ect. will push it.

(Alot of us) have upgraded our power supplies. Have seen 550 to 1200W going in with out any problems. Replaced mine with a CM 850W Modular.

Worked great and haven't heard of problems with others either, Other than could only use 3 of the 4 screw for holddown on some units. No biggie!

Now my 850W is in my new( Home built 4.2 rig) and 475W back in the XPS435T/9000.Good machine but handicapped for the price.

Never buy another pretty much non upgradable machine again.:emotion-45:


My two cents worth.


2 Bronze
2 Bronze

Thanks Irocing for the reply and info, I read through Cooling Masters specs and bookmarked them..

Did you test this PSU/9000 box  with a regular APC UPS?

I'm trying to decide if I should upgrade the Psu now or just find a UPS that works with the OEM PSU, since I'mnot planning to upgrade my Video right now.


I'm hesitant to install a new Psu on  a brand new PC so soon, and worry that Dell's warranty may be void.

.PS: Interesting that you and others find the 9000 to be non-upgradable, I thought it was and that's why I got it, but goes to show how complicated all this 'hardware' stuff has gotten, I researched  for quite a while before pulling the trigger but obviesly still missed important info.


3 Silver


 As to the UPS, have a Belkin that have used for years for other computers and not a problem at all.

Was not able to use it for my new build though because of power requirements when overclocking.

Works fine for the Dell though.

As to upgrading your power supply see no reason for you to upgrade unless going for a power hungry

video card and alot of drives and devices. The 475 seems to be a good unit.

 Went a few rounds with Dell when I purchased it as was not quite told the truth about things like overclocking,

memory speed upgrades and a few other items. Purchased my 435T/9000 when they first came out and suppose thier

(Salesmen and techs) I talked to at the time where not, shall we say, Up to speed on it.

Almost sent it back but needed one badly at the time.

 Just got done building my own computer from scratch and wish had done it from the start.

Worked out good though as the Dell is the other halfs now and she really likes it.

 My new unit is sitting at 4.2 rock stable and can go higher, unlike 2.6 and bios locked Dell.

Running #2 video cards and could run #3 if wanted to. Dell #1.

Can run any speed memory out there, will take the new 6 core processor,Sata 3, USB 3.0 and the list goes on.

Thats upgradability. And just below the initial cost of my Dell.

Al though does not include the cost of the power supply or new vid card I upgraded to in the Dell.

Now Dell back to original.

 Don't get me wrong, the XPS435T/9000 a very good machine for the average user.

Hope this helps. 

3 Silver

I realize this post is a little dated, but it still contains good information. I took delivery of a XPS 435T refurb this almost past summer. The PSU situation I solved. After experencing the heat given off this machine I looked for answers. I replaced the PSU with a Corsair TX 650W, standard ATX unit.. Heat is down and the computer is more responsive. Heres the fab work. Mounted the PSU towards the top of the case using the holes that would pin. Elongagated one hole towards the 10 oclock position as needed. The screw covers the complete hole, out of site. The other non pinning hole was moved up aprox 1/8" to 3/16". This left a gap and the unused hole. A 5/8X 6" piece of aluminium .030 thick to start covering this mess. Trimming to length (width of the case) I was able to tuck the bottom of the filller piece into the panel supporting the rear case fan. The ends of the filler are not seen -covered by white sides of the case. Lossen the PSU screws and it will also tuck under it. It looks like the filler belongs there. The PSU does not sit on the side rail inside, in this configuration. So I took some square aluminum (1/2") tube and cut it in 1" lenghts (2 pieces).Placed one at the back and one farther in on the rail. Loosened up the PSU screws and the blocks slide in with a dab of epoxy on each. Tightened the PSU up. No rattles or other.                              

I see reports of these machines running 50C plus, Mine did also. I solved this problem by replacing the Intel CPU fan and heatsink with the crazy tube, with a copper tube and fan arrangement. Unloaded I will see 30 to 34C. Loaded 40 to 42C. I chose a Rosewill unit and installed one on my LGA 775 machine with the same results. 2 extra 92mm fans were added. One in the Flex bay and the other in the now vacant left side vent pulling air in connected to a variable speed controler. The run on 1/4 throttle. Yes the flex bay holds the attachment for reading motherboard and hard drive temps. Hope these are helpful.

2 Bronze
2 Bronze


I also recently purchased the XPS 435T as a refurb. I've had it for over a month now and I like it alot. But I too am indeed getting VERY hot readings from my CPU. Right now, it's idling at 55c. And if I run DVDFab (DVD ripping/video convertion) which takes advantage of all four CPU cores, it will almost max them out at 99%. Very quickly, the temps SKYROCKET to up to 92c. That's correct 92c. So this obviously has me worried makes me have to always think twice now before I start doing heavy CPU intensive stuff because I don't want to fry the thing, which kind of defeats the purpose of me getting this new beefy PC if i can't take full advantage of it.

I've considered replacing the fan/heatsink, but I'm kind of a novice pc user - not a massive noob beginner, but not a geek master either. I've never built a pc, but I've installed hard drives, ram, video and audio cards several times on mine and family's pc's, but never a CPU heatsink which I would be nervous about. Mainly  the idea of removing the old thermal paste and applying the new is what gets me neurotic because it's not just unplugging and plugging something - there is a margin of error there - you can apply too much or too little of the paste. Also, perhaps a bigger worry, is about how changing a CPU fan will interact with the Dell BIOS. I wonder since it's a different fan with potentially different specs like the fan size and RPMs, will it result in strange behavior of the fan? For example, will the fan spin at much higher RPMs than necessary, or spin much too slow, or stop the pc from booting. I remember reading on some post that this might be a problem if the BIOS expects the fan to spin at a certain RPM during boot and will just shutdown or keep restarting if the replacement fan doesn't behave like the Dell BIOS thinks it should.

Anyway, if you say that your Rosewill heatsink works perfectly, then I might want to get the exact same one as you. Could you give me a model number or a link?

And about the two extra fans you installed: I looked in my case, but I didn't see any extra power connecters available. What did you hook them up too? Putting in another fan or two in just the way you described was also something I was considering, but I just assumed it wasn't an option since i couldn't find any spare power connections.



Latest Solutions
Top Contributor