I am looking into upgrading a few things on my Studio XPS 435t / 9000. Exactly what processors are compatible with my motherboard?
We do not suggest upgrading the processor on the system, however I have mentioned the processors compatible with Dell Studio XPS 435t / 9000:
Intel Core i7 920Intel Core i7 940Intel Core i7 965
Also, ensure that you update the BIOS before upgrading the processor. Click the link mentioned below for the BIOS:
NOTE: Ensure that the system does not turn off during BIOS update.
For more upgrades, click the link mentioned below:
Thanks & RegardsManshu S#iworkfordell
Dell Studio XPS 435T/9000
Since there doesn't seem to be a good consolidated list of possible CPU upgrades for the Dell Studio XPS 435T/9000, thought I'd put one together here. Although I've listed below the Intel series that have shown to work, I only focus on the top CPUs in each series since that's likely what you'll want to upgrade to. Also, for reference I've listed approximate prices on ebay, to give you an idea of cost. Prices can vary widely depending on where and from whom you buy from. Ebay seems to be cheapest, but caveat emptor on Sellers.
Determining what CPUs work can be based on several things: 1) Dell's BIOS update description listing adding CPU series support, 2) my and others experience on web trying different CPUs, 3) user benchmark sites and 4) description of sales of used 435T machines. Generally, if the fastest CPU in a series works, the entire series is assumed to work.
Intel Xeon processors that work for the 435T are cheap (often half the price of corresponding retail/consumer i7 processors) because businesses are replacing their systems and their older Xeon processors are being sold in the secondary market. Note Intel Xeon branded CPUs generally contain extra features for business users that retail/consumer CPUs do not. Since their base feature set is usually the same, a Xeon processor can often replace its corresponding retail/consumer processor (but usually not the other way around). The extra features just aren't used in the 435T.
First some fine print regarding Turbo Boost and SpeedStep. Although Dell added support for Gulftown Xeon processors (and by extension Westmere EP) in the A15 BIOS (Note "Update BIOS to support new intel CPU (Gulftown) launch" under "Fixes & Enhancements" section), it appears they never fully tested it and/or provided a followup BIOS update to fix issues with Turbo and SpeedStep. There is no Turbo Boost for any of the Gulftown and Westmere-EP series when running in the 435T - max processor speed is the base speed. On average this results in a performance loss of about 0.133 GHz. Also, there's an issue with SpeedStep (idling at a lower-power processor speed under low/no load). It works for a fresh boot/reboot session, but not after the processor resumes from Sleep. After Sleep speed is stuck at base speed, providing no energy savings.
Below is from a W3690 (Westmere-EP Xeon branded i7-990X, more or less) after a reboot. Note base clock is 3.46 GHz (x26). Some cores are idling (x12), but no cores ever Turbo, neither at x27 (3.6 GHz), nor x28 (3.73 GHz). (Screen capture is of HWiNFO64 showing dynamic CPU core speeds.)
After resuming from Sleep, all cores are stuck at base 3.46 GHz (x26) speed, regardless of CPU load. Again, no cores Turbo.
What this means is a 4-core Gulftown/Westmere-EP CPU at 3.46 GHz will have about the same performance as a 4-core Bloomfield CPU at 3.33 GHz, since it can Turbo to 3.46 GHz when all cores are under load. Keep this in mind if selecting a quad core upgrade. Since the only hex core processors available for the 435T are Gulftown/Westmere-EP it means there are no 6 core CPU options with working Turbo Boost.
I've personally noticed Turbo not working with an i7-980 and W3690, but you can check this yourself by scanning user benchmarks for 435T on UserBenchmark. If you drill down to the CPU for a 435T using a Gulftown/Westmere-EP processor (here's an i7-970) you'll see the average Turbo is always the same as the base CPU clock (3.2 GHz for both for the i7-970). This isn't the case for Bloomfield processors, nor for example with Dell's follow-up machine, the Studio XPS 9100, where Gulftown/Westmere-EP CPUs can be seen if you drill down here to have an average Turbo higher than base clock, as they should.
With that out of the way, here's the list. For reference, many 435T's came with an i7-920, a quad core which runs at 2.66 GHz. Note where I could find user benchmarks for a specific CPU I've linked to them. For both 4 and 6 cores, I've highlighted top CPUs in red, one tier down in blue and what I consider a good value in green. Only the least expensive CPU at a performance point in each tier is highlighted.
Top quad core CPUs that work or should work in 435T/9000
Bloomfield, i7-9xx series
Bloomfield, Xeon W35xx series
Westmere-EP, Xeon X56xx series, no Turbo with 435T
Unconfirmed quad cores
I have no confirmation that the Gainestown Xeon W55xx series works with the 435T. However, it uses the same LGA 1366 socket and came out about the same time as Bloomfield. There's a report of a X5570 Gainestown Engineering Sample working in a 435MT (Mini Tower - different machine from 435T/9000, but released about same time) here. It worked fine until a BIOS update caused it to fail to boot (likely because it was an early prototype), although it still Posted (meaning BIOS still recognized it). The X5570 at 2.93 GHz is one step down from the W5580 and W5590 below. Dell's follow-up machine to the 435T, the Dell Studio XPS 9100, also has confirmation of someone running a Gainestown X5550 (2.66 GHz) on Geekbench 2 here. I'd go with the W35xx Bloomfield series instead, but if unavailable the W55xx series might be worth a try.
Gainestown, Xeon W55xx series, quad core - may or may not work with 435T, Turbo likely works
Top 6-core CPUs that work or should work in 435T/9000no Turbo with 435T
Gulftown, i7-9xx series
Gulftown, Xeon W36xx series
Westmere-EP, Xeon X56xx series
*UserBenchmark results for Dell Studio XPS 435T/9000 - if CPU not listed under "CPU" tab here or here (clipped to top 11 results), then scan all User Benchmarks for the specific CPU here and here.
I have a new EVGA GeForce GTX 970 (04G-P4-3975-KR model) waiting to go in mine. Chose that model partly because it runs close to reference clocks, but should still have some headroom for overclocking. Would like to stay within limits of original PSU if possible, undervolting GPU if necessary. Could always upgrade PSU later if I need it.
BTW, I'm currently having an issue with Turbo and SpeedStep not working after a clean install of Windows 7 SP1. CPU speed as report by CPU-Z, HWiNfO, HWMonitor, etc. is always locked at 3.3GHz. On Balanced Power Option it should clock down and I think on both Balanced and High Performance one or more cores should clock above 3.3GHz. I'm not sure if this was an issue before or just started after the clean install.
If you do re-commission your i7-975X, could you let me know if Turbo and SpeedStep work on yours? Thanks!
Did some upgrades (CPU and GPU - EVGA GeForce GTX 970 04G-P4-3975-KR - still on stock motherboard and PSU, plus upgrade to Window 10) and successfully tested several Intel Xeon CPUs with the Studio XPS 435T/9000. These are relatively inexpensive on ebay.
Below are good performing Xeons that should work with 435T - ones I actually tested successfully with 435T in bold (HWiNFO screenshots follow). For reference, many 435T machines came with an i7-920 (4 cores, 2.66 GHz):
Everything seems to work fine with the Xeons and the XPS 9000. Only caveat is that with the 6 core processors (including the i7-980 and likely i7-970, i7-980X and i7-990X) Turbo Boost does not work (CPU doesn't go beyond stock speed) and after resuming from sleep CPU doesn't go below stock speed (meaning Speed Step doesn't work). Turbo Boost is only about 133 MHz with multiple cores, so not too big a loss. Conversely, with the 4 core Xeons, Turbo Boost seems to work fine and there is no sleep issue.
Screen shots of Xeons that I ran with the Dell Studio XPS 435T/9000 :
Intel Xeon W3565:
Intel Xeon W3580:
Intel Xeon W3690:
techgee - is this the best/most powerful video card this original PSU can handle?
Sapphire HD 7850 ?
Does it matter if CPU is I7-980 vs I7-980x for Dell? There is no multiplier? and motherboard is limited to 4.8GT? I just looked on Ebay and there are some good bargains for either Xeon or I7 family.
Boriszima, no a Radeon HD 7850 isn't the best in the 7000 series that 435T can handle on original PSU. Not sure what is, but if I remember correctly a 7870 would work. I later upgraded to a GeForce GTX 970 on original PSU, as you can see above (here).
For a 435T an i7-980 and i7-980X would have about the same performance. Since the 435T can't be overclocked the unlocked multiplier in the i7-980X doesn't help. Also, bus bandwidth is so high that 4.8 QPI vs. 6.4 QPI doesn't matter either.
What thermal paste application method did you use when installing the w3690 in your xps 9000?
Did you change the stock heat sink/cooling? I wonder if the lack of SpeedStep can cause heat issues. Someone on YouTube ended up with too much heat after installing a w3690.
Also, did you ever get around to overclocking with older versions of Intel XTU?
Finally, did you end up using a SATA PCIe card to connect your SSD to the PCIe x8 slot? If so, which one?
Thanks for all your posts, my major upgrades have been based off of them!
Thanks, glad you found some of my posts useful!
I've used Gelid GC-Extreme (aka GC-3) and Arctic MX-4, both electrically non-conductive, seemly durable, good heat conduction and not too expensive. Used the 5 dot method to ensure coverage (even if heatsink comes down at an angle) without an air pocket. 'X' method resulted in too much paste (bleeds out around edges). One dot method is ok, but heatsink needs to come down parallel to CPU to ensure coverage isn't lopsided. When heat sink and CPU are pressed together and seated the ideal is as thin a coat as possible (meaning heat sink and CPU are as close together as possible) and coverage of the entire rectangular contact area between them.
I'm using the Intel DBX-B CPU Cooler that came with the i7-980. It's more than adequate. I posted about it on Dell's forums here. You can get one cheap on ebay (it's heavy, watch out for shipping costs). Some reviews of the DBX-B Cooler here, here, here, here and here. Has two speed settings - I leave it set on the lower speed 'Q' or quiet setting.
I decided trying to use older versions of XTU not worth it, especially since current XTU seems to allow for "overclocking" Turbo Boost, even on OEM motherboards like Dell's. However, it seems to have enough bugs that I don't recommend it.
I'll post my experience successfully overclocking the 435T on the 435T/9000 and 435MT Overclocking Potential thread.
I never added a SATA PCIe card partly because I don't think you can boot off it and I think it'll be at least partially bottlenecked even in the x8 slot, but mainly because I decided to reserve the x8 slot for a future upgrade from a current USB 3 PCIe card to one that supports USB-C.