Overclockable Dell computers.

[Retrorockit]

Re: Overclockable Dell computers.

Yes BTX is very old stuff. When the memory controller moved to the CPU it lost it's purpose, and never was accepted by the aftermarket anyway. But bad caps were common on them. While overclocking old computers may or may not be useful, it may tip the csales a little in deciding whether to save a MB or not.
I have a tutorial on this at Tomshardware and just updated it with some OC benchmark scores, and a video of doing a software fsb overclock.
https://forums.tomshardware.com/faq/...uters.2528664/
I agree that the Pentium D computers are fun. Many later office computers had a 95W CPU limit that keeps the Extreme series CPUs out. Pentium D machines needed 130W so if they can run Core2 Extremes the VRM and also clock speed are built in.
Here's the leader board at CPUZ for QX6800.
http://valid.x86.fr/top-cpu/496e7465...322e393347487a
0WG864 is a Dell Dimension E520. If you look at the dates you can see it was in 2nd place there in 2015 when I did that. 3rd place for almost 2 years.
For actual performance the T3400 workstation is better withQX9650 and dual GPU support. I've picked up T3400 MB for $14 each.

[piernov]

Re: Overclockable Dell computers.

I personally don't really find overclocking on older machines worthwhile (well, even on newer in most cases) and it's a bit unfortunate to have to rely on a Windows software but for fun why not.

But still Throttlestop can be useful in some very specific cases. For example had a 945GCT-NM board (from a PowerMate VL260) that originally came with a Pentium D IIRC. MCH, voltage regulator and BIOS actually support Core 2 Duo, but it's limited to 800MHz FSB. So without doing FSB mod and so lowering CPU core freq, you have to stick to 800MHz FSB CPU, which are either the early Core 2 Duo, or the Pentium Dual-Core. The latests Pentium Dual-Core perform much better than the early Core 2 Duo, and for some reason this board can actually boot 45nm CPU. The Pentium Dual-Core E5800 is a very good choice here.
But, there is a catch. BIOS is buggy or 45nm CPU support not implemented properly, dunno. Everything reports properly "on paper" (BIOS info, Windows system info and task manager…), but it's very sluggish. Then you check with Throttlestop and you realise it's stuck at x6 multiplier instead of x16. So 1.2GHz instead of 3.2GHz. Only solution I found is to use ThrottleStop to force the multiplier at boot to x16 (SpeedStep has to be enabled, otherwise multiplier is really stuck at x6 and ThrottleStop cannot change it). Had to tweak some stuff to get ThrottleStop to automatically apply settings transparently using SYSTEM account after boot or resume from hibernation.

Downside is that it only works on this specific OS installation after the tweaks. If you boot any other OS
(a Linux live for example) you'll be stuck at 1.2GHz as well…
It's still a substantial improvement over any 65nm CPU.

Similar situation happens on some HP machine, I think it was the dc7700, where due to some BIOS bug the frequency of E7xxx CPU is halved whereas E6xxx work properly. (btw they could work with Core 2 Quad if the BIOS didn't disallow it as well)


The BIOS situation is really a nightmare with those older machines unfortunately. It'd be wonderful to have an open BIOS with every CPU initialization code and working on all boards just so you can upgrade them. coreboot is not quite there yet… Lots of Pentium 4/Pentium D boards could support better Pentium D 9xx/Core 2 CPU , sometimes after a few hardware tweaks if they had proper BIOS support.

[momaka]

Re: Overclockable Dell computers.

I don't have much to offer in the way of board level repairs. I hope this isn't too OT for this forum.

Not at all. In fact, I learned about a new piece of software from your post today! - Throttlestop. Will definitely give it a try, as I still have many computers from that era stick kicking around. So thank you very much for sharing this information!

[Retrorockit]

Many Dell computers can be upgraded beyond what they were offered with and even overclocked in many cases. This may make repairing one of these more viable than it would seem. I've been playing with the BTX versions so much of what I say will be referring to those.
Of the BTX Optiplexes, most of them have a 95W CPU hard limit. Typically a Q9650 is the maximum, For single thread Apps, an E7500 2 core can be tape modded to 3.66GHz.
The exceptions are the Opti 745 which due to PentiumD suppport can support a QX6800 and can be overclocked using Throttlestop 6.0 software.
The Optiplex 380 can run an X5470 Xeon with a BIOS mod for 3.3Ghz. It can also run 2x4GB DDR3 1066 RAM.
Other Dells that can run the 65nm QX6800 and overclock are the-
Dimension E520,9200,9200C XPS410,210 These have 4 phase VRM and can get to 4GHz at times.
Some other XPS and workstations can run the unlocked 130W QX9650. 4.15GHz is common.
XPS420, XPS430, Precision T3400 (dual GPU )XPS630
The Precision T3500 can run some of the unlocked Xeons and overclock them. W3570,W3580 4 core Nehalem, and W3680,W3690 6 core can be Throttlestop overclocked, and 3 channel RAM makes performance worthwhile.
Due to larger memory modules becoming available over time almost all of these computers can run 2x the RAM they were originally offered with.
Userbenchmark.com is a good place to look at a system and see what CPUs and RAM capacity others have been able to use.
I don't have much to offer in the way of board level repairs. I hope this isn't too OT for this forum.