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Fellow Gerbils, I'm in the process of building a new video/gaming workstation. I've hit a potential snag in the process.
As you all (probably) know, it's becoming increasingly difficult to find motherboards with two PS/2 ports on them these days. So, I find my self in a bit of a pickle, because I refuse to give up my PS/2 keyboard and mouse. Also, my 4-PC KVM is also PS/2 only. The research I've conducted makes it painfully obvious, that it would extremely expensive (not to mention a royal pain in the buttocks) for me to try to replace all those components. So, I've come to ask (especially those with those older mechanical keyboards) if any of you might be kind enough to point me in the direction of a correct PS/2 to USB adapter, so I might side step this whole issue.

In looking through many of the customer reviews (especially at newegg), I find myself increasingly nervous on making a purchase of any of the adapters, as it seems a vast majority of them have compatibility issues.

My requirements are thus:

1) The adapter needs to work with my KVM (Trendnet TK-401R)
2) The adapter needs to allow me to get into the BIOS and do what's necessary in there
3) This one seems to be the most difficult to accomplish (based on my reading): The adapter needs to be able to allow simultaneous keystrokes (both additive and subtractive), ie. gaming situation

With that stated, I know that many of you have clung to your old mechanical keyboards, so please tell me your solution to getting your older keyboards and mice to work with these new motherboards that have banished PS/2 ports to history.

Thank you.

Try these.

Riviera74: Thanks for the link, however, many of those same adapters are sold at newegg, with customer reviews claiming to have issues.

I was kind of hoping that a fellow Gerbil would point me to an adapter that they have had personal success in making work in the situations I've outlined above?

But thanks, none the less.

Yeah, the main thing you want is you want an adapter with a built-in microcontroller. Not just a regular plug. Those plugs that you sometimes get with keyboards and mice only work with THOSE keyboards and mice and depend on the device having a controller inside that detects what interface to use.

At work I bought these since our HP servers no longer have PS/2 ports and our 16-port KVM doesn't do USB:

http://www.newegg.com/Product/Product.a ... 6812119237 (works fine on 4-port and 16-port KVM, a spare)
http://www.newegg.com/Product/Product.a ... 6812156019 (worked with a cheaper KVM, not with the 16-port)
http://www.newegg.com/Product/Product.a ... 6812196234 (in use, works fine on 4-port and 16-port KVM)

So these are going from USB computer to PS/2-based KVM. I left feedback on all of these (the HP DL360 G7 entries). They had the right balance of being cheap and hopefully working. Were I to get more, I'd go for the Cables 2 Go one because it worked nicely and it's in a sexy black color. Because, you know, that is really front-and-center at the back of a crowded server rack. Yup.

I do notice that the plastic casing doesn't look identical to what's in the pictures. I forget if it was the same way when I ordered before, but just minor differences. So there may have been revisions. Still, I stick by my recommendation. Buy one or two and check 'em out and return them if they suck.

Ah, I do notice that I didn't address the simultaneous keystroke issue. I think that will be more a function of the keyboard controller than a PS/2 to USB converter. I have an old Northgate Omnikey/101 mechanical keyboard and I've kept it around because it's one where you can hold down EVERY key and they register. And it has a buffer too so if you are waiting for a program to catch up, it keeps feeding the next keystrokes when ready. Granted, more of an issue when I had it hooked up to my 486DX/33, but still nice.

Anyway, I used a converter bought from a local Micro Center and the performance is the same. So either I lucked out and got one that preserved the performance or registering keypresses is independent of the conversion. Honestly, from what I've researched in that, I believe it's a function of the keyboard more than anything else.

That is to say, I didn't try that test on our server KVM keyboard (it's built into a rack-mount unit) or on the cheaper KVM. Plus, all the keyboards here at work stink so it wouldn't have magically made 'em better, anyway. All them cores I tested on might be good for servin' but man, that integrated video really has issues with Crysis!

Also also you'd think you'd be set with one of these: http://www.newegg.com/Product/Product.a ... 6812107957

...but some of the reviews really don't paint a positive picture. Still, same brand, maybe they were made in the same overseas sweatshop?

Scrotos: Thanks for the info (and links). As luck would have it, I'm actually awaiting a reply from Cables2Go, about that very model you linked to. My fingers are crossed that they'll be able to give me confirmation.

You've given me confirmation on KVM and BIOS concerns: Thank you.

Scrotos: Unfortunately, the Trendnet adapter you linked to, I now have confirmation (direct from Trendnet tech support) that it cannot be used to enter the BIOS because it needs the OS to load drivers in order to function.

Scrotos beat me to it, but:

riviera74 wrote:

Try these.

The problem, as the OP mentions, is compatibility issues: many of those may work fine for PS/2 mice, but they fail totally and utterly for old PS/2 mechanical keyboards because they're passive adapters without the electronics needed to make older PS/2 keyboards work. The two adapters that are known to work reliably are the Ziotek "blue cube" (usually combined with a short USB cable like this for convenience) and the Belkin F5U119-E (note the -E suffix; other F5U119 variants don't work). There's an entire wiki out there devoted to this particular wrinkle (I have it bookmarked on my home machine but don't have it handy ATM, but I think I got the link originally from an earlier discussion here on the forums so somebody can probably post it if I don't get a chance to search here for it.)

UberGerbil: Awesome. Thank you.

I have had this problem before and can confirm that the Belkins UberGerbil linked are compatible with all the KVM's I have had at work, even for non-OS things like PXE boot menus and RAIDBIOS stuff. Servers just stopped coming with PS/2 ports and there was no way I was chucking out £1000's of perfectly good KVM switches.

I'm not sure about n-key rollover but perhaps Scrotos is onto something with it being down to the hardware not the USB converter.

Chrispy_: Thanks - further confirmation.

UberGerbil wrote:

The two adapters that are known to work reliably are the Ziotek "blue cube" (usually combined with a short USB cable like this for convenience).

The guts of that USB widget may be soldered into the controller board of a Model M to make it native USB.

Captain Ned: OK, that's a tad extreme (for me anyway), but good to know.

My solution to this exact same situation was to run just the keyboard and monitor through the PS/2 KVM, and use a separate cordless USB mouse for each system.

Edit: Regarding the simultaneous keypress issue, the standard USB keyboard protocol allows 6 simultaneous keypresses (plus modifiers). So if you have an n-key rollover PS/2 keyboard and run it through a USB adapter it will essentially become a 6-key rollover keyboard. This is an inherent problem with the USB keyboard protocol, not a defect in the adapter.

Just Brew it!: I guess a fall back option would be to use the one PS/2 port (on the motherboard), and I'd just need to adapt the other device to USB.